Boilers and HVAC Building Automation Systems

With the newest state-of-the-art sensors, direct digital controls and computer driven expert systems, buildings now can be completely automated and remotely controlled. This article will review what such systems and their operators can and cannot do, what new risks can be created for the boilers in such buildings, and how to reduce and control those risks.

Benefits of automation

Intelligent buildings today use a building automation system (BAS) and other systems to operate HVAC, boilers, chillers, lights, elevators, building access fire protection and other systems to achieve the twin goals of efficiency and comfort.

A BAS is defined here as a system of sensors, pilot devices, logic elements, controllers, peripheral computers, and monitoring equipment providing data to a central computer for energy-efficient control of a building’s internal environment while also providing maximum tenant comfort and equipment reliability.

BAS can deliver energy savings, comfort and maintenance/reliability benefits. These benefits cannot be achieved, however, unless the systems are properly integrated. The system designer must anticipate and overcome the risks outlined below.

Thermal shock

When boiler controls are improperly integrated with the BAS, thermal shock can occur in several ways.

The most common is low return water temperature. In a recent claim, a cast iron hot water boiler suffered a cracked section because of cold water returning from the system. The building was a single-story school, with portions of the building distant from the boiler room.

During the fall, the BAS was programmed to reduce the temperature setpoint on weekends. Water in the zones serving remote areas cooled, and when the BAS attempted to bring the building back to normal occupancy temperatures, a slug of cold water cracked the hot boiler sections.

The problem was solved by putting timers on the zone valves to prevent the simultaneous opening. Controls also were added to maintain a minimum floor through the longest loops during reduced temperature operations to maintain a minimum temperature.

In another case, a store chain reported damage to boilers and air conditioning equipment due to thermal shock when the BAS alternated between heating and cooling. This situation was made worse because all the store locations around the country were connected to a central BAS.

The central BAS computer did not adequately allow for transition from heating to cooling operation and vice versa, resulting in boiler damage and business interruption.

Another form of thermal shock can occur in systems that use a three-way bypass valve. When controlled by outdoor air temperature, these valves allow a high bypass, with reduced flow through the boiler. This reduces the temperature delivered to the loop, thereby saving energy.

The problem occurs when the control is so aggressive that the boiler water stratifies the same way water stratifies in a water heater. In situations where the boiler is called on to deliver only minimum input, the burner will cycle frequently. Since the overall temperature is low, the metal is subjected to much higher stresses than intended or designed for by the supplier.

Thermal shock also has occurred in boiler rooms having outside air inlet louvers controlled by the BAS. Cold outside air entering the boiler or equipment room will chill the boiler. If inadequate precautions are provided, thermal shock, freezing or condensation will occur.

Single-pipe heating and cooling systems area also subject to thermal shock. Single-pipe systems — one piping system for heating and cooling — sometimes are selected for low initial cost. Should both heating and cooling be called for within a short period of time, there is a good chance that chilled water will be admitted into the boiler. Serious thermal shock will result.

Two-pipe systems — using separate piping circuits for heating and cooling — do not completely eliminate this risk. If the BAS incorrectly sequences air handling units and if both heating and cooling coils are in the same unit, air cooled by the refrigeration coils will cool the heating coils. This also will cause cold water to return to the boiler.

Another more common event occurs when the BAS calls for 100 percent outside air to save cooling or heating energy. This usually occurs in shared spaces of buildings that do not require heating or cooling for comfort. Spaces such as foyers, lobbies, hallways or large conference rooms frequently receive 100 percent outside air to address indoor air quality concerns.

The heating coils in the air handling units can be subjected to low temperature. When the boiler starts or the local zone calls for heat, the cold water will shock the boiler.

In spaces requiring very strict temperature and humidity controls, simultaneous operation of the heating — temperature control — and cooling systems — to reduce humidity — is needed. Careful attention to the programming of such heat/cool operation is necessary to avoid the potential for cold water return to a hot boiler.

Condensation

When boilers cool below the dew point temperature of the combustion products, flue gas condensation will occur during the boiler warm-up, causing corrosion on fireside surfaces, breeching and stacks.

Corrosion is another leading cause of boiler accidents. Much of the corrosion can be avoided if the BAS is programmed to maintain boiler temperature at or slightly above the flue gas dew point.

Boiler start-up

When a boiler is first started from a cold condition, both the metal and water are cold. If the boiler is designed to adjust firing rates in response to load changes, it is very important to heat the boiler slowly.

The metal structure must be allowed to gradually absorb the stresses that develop as the metal expands with temperature. Most boiler manufacturers include low fire hold into their boiler controls to provide boiler warm-up. BAS programming must not compromise this protection by premature transfer to high firing.

Multiple boilers (Modular)

For buildings with multiple or modular boilers, the hazards discussed above are more difficult to handle. In such cases, BAS programming must recognize the practical limits of boiler operation for all units.

Other concerns

In addition to the mechanical aspects already discussed, there can be other concerns with control system integrity. A BAS is comprised of sensors, pilot devices, logic elements, controllers, peripheral computers and monitoring equipment. All of these devices are sensitive to some of the following conditions.

Electrical transients

A number of claims have recently been reported involving failure of electrical and electronic devices caused by electrical transients. Common disruptions stem from lighting, internal power fluctuations, harmonics and electric utility problems. Without proper protection, an otherwise harmless power fluctuation can result in damage to the boilers if the BAS fails.

Major utility power problems are infrequent. Lighting arresters, surge protection and current controls have made power in the United States very reliable. One source of localized disturbances is not uncommon, however.

Short duration voltage collapse — a few cycles — can occur when utilities attempt to regulate power factors by compensating for inductive loads with large capacitor banks. When the capacitor bank is engaged, the current inrush causes the voltage to sag, which can cause localized disturbances in the power system.

Boiler/BAS Solutions

CONSIDER THESE RECOMMENDATIONS to address common boiler problems related to BAS:

Thermal shock

• Prevent cold water return by installing three-way mixing valves as a way of limiting the boiler inlet water temperature.


• Consider a small blending pump to prevent temperature stratification in the boiler.


• Control the low fire hold to warm the boiler according to boiler manufacturer guidelines.


• Avoid high fire cut-off when zones are satisfied to avoid rapid temperature change.


• Don’t overlook the air side as a potential source of thermal shock.

Condensation

• Avoid control logic that will increase the frequency of boiler cycling.


• Avoid contact of humid outside air on cool boiler surfaces, or keep the boiler warm.


• Maintain minimum boiler temperature at or above flue gas dew point.

Electrical transients

• Properly ground not only the BAS but also all other equipment. Follow the manufacturer’s instructions.


• Isolate AC power connection to electronics using isolation transformers or equivalent devices.



• Maintain minimum boiler temperature at or above flue gas dew point.

Recommendations

This article has covered areas of concern when integrating heating and cooling equipment with automatic building controls. BAS control programs must recognize the operating limitations of all controlled equipment, as well as the customary energy optimization, HVAC comfort, and building security objectives.

Building designers and owners and maintenance and engineering managers should always follow the recommended practice of the equipment manufacturers. BAS have the ability to control and monitor equipment and alarms from remote locations. Many states have laws requiring boiler operators to be on site in certain situations.

The ability of the BAS to sound alarms based on preset conditions with actions implemented from a remote location should not replace the actions taken by qualified operators on the scene.

DtiCorp.com is Introducing the New Honeywell L7224R1000 Oil Electronic Aquastat Controller

Fort Lauderdale, FL – Popular Honeywell online retailer DtiCorp.com (http://www.DtiCorp.com) is introducing the brand new Honeywell L7224R1000, 120 Vac Oil Electronic Aquastat Controller with Outdoor Reset Module. The L7224 and L7248 Oil Electronic Aquastat Controllers are primary safety limit-rated devices designed for use with oil fired boilers with line voltage burners and circulators. Many boilers do not include wiring or control compartments as part of the design, but are provided with an integral, replaceable, immersion well that is the mounting hardware for the Aquastat Controllers. Wiring to the other controls is done through flexible metal conduit. For boilers that do include a remotely (flush) mounted control, the wiring may be completed with conduit or routed behind the boiler sheet metal.

A separate electromechanical high-limit is not required in a system that uses this control to meet Underwriters Laboratories Inc. requirements for oil-fired boiler assemblies, UL 726. On the L7224 models, the High Limit, Low Limit, Low Limit Differential, and Anti Short-Cycle time can be adjusted to the setting recommended by the boiler OEM. On the L7248 models, the High Limit, and Anti Short- Cycle time are also adjustable, see “Adjusting Settings”. The overall range of the High Limit is from 130° F to 240° F (54° C to 116° C). Select devices may have different ranges. Some models have limited ranges on the High Limit setpoint; this limited range is listed on the device label.

Some models also have a Low Limit and Low Limit Differential adjustment. The range of the Low Limit is from 110° F to 220° F (43° C to 104° C). Select devices may have different ranges. The L7224A and L7248 are designed for use with 24 Vac electronic and electromechanical thermostats or EnviraCOM enabled thermostats, and have screw-type terminals for easy field connection.

Features:

- Application: Oil Aquastat Controller with Outdoor Reset Module

- Operating Range, Low Limit (F): 110 F to 220 F

- Operating Range, Low Limit (C): 43 C to 104 C

- Operating Range, High Limit (F): 130 F to 240 F

- Operating Range, High Limit (C): 54 C to 116 C

- Differential Temperature (F) – High limit : 5-20 F adj.; low limit: 10-25 F adj.

Specifications:

- Electrical Ratings (burner AFL): 7.4 A @ 120 Vac

- Electrical Ratings (burner ALR): 44.4 A inrush

- Electrical Ratings (circulator AFL): 7.4 A @ 120 Vac

- Electrical Ratings (circulator ALR): 44.4 A inrush

- Voltage: 120 Vac

- Frequency: 60 Hz

- Maximum Power Consumption: 2000 VA

- Dimensions (in.): 7 1/8 in. high x 4 1/4 in. wide x 2 5/8 in. deep

- Dimensions (mm): 181 mm high x 109 mm wide x 67 mm deep

- Mounting: Well mount, horizontal or vertical position, or flush mounted remote from the well.

- Operating Humidity Range (% RH): 0 to 95% RH, non-condensing

- Maximum Ambient Temperature (F): 150 F

- Maximum Ambient Temperature (C): 66 C

- Minimum Ambient Temperature (F): -30 F

- Minimum Ambient Temperature (C): -9 C

- Approvals, Underwriters Laboratories Inc: Recognized

- Includes: W8735S1000

About Us: DtiCorp.Com (http://www.DtiCorp.com) carries more than 35,000 HVAC products, including industrial, commercial and residential parts and equipment from Honeywell, Johnson Contols, Robertshaw, Jandy, Grundfos, Armstrong and more. Our online catalog is easy to navigate and search, and all products have a picture and a description. If a customer has any questions about a product, they can call 800-757-5999 and speak with one of our product experts. Our mission is to offer the best prices anywhere to our customers.

Julian Arhire

Manager DtiCorp.com

Phone: 954.484.2929

Fax: 954.484.5155

Web: http://www.DtiCorp.com

###

What Are The Rooftop HVAC Units?

When rooftop units were first introduced some 40 years ago, they were considered by system designers and building owners to be a bare bones, low cost, simple solution to low-rise building HVAC needs. Low cost was the primary driving force for both manufacturers and users. But while they were popular with designers and owners, many maintenance managers considered them nightmares: difficult to service, prone to breakdowns, inadequately protected from the elements.

Today, everything has changed. Gone is the concept of one size fits all. Buyers have more options, including practically all of the same features found in other types of building HVAC systems, from economizers for energy conservation and prewired interfaces for building automation systems to heat wheels and other heat recovery devices. No longer can the systems be labeled as bare bones.

What has contributed to this change has been a shift in focus from first costs to life-cycle costs by both manufacturers and users. The result has been the development of new rooftop systems that include features to make them more efficient and easier to maintain.

The typical rooftop unit today comes in one of two configurations: single-zone or VAV. Single-zone systems remain the more widely used. They are low-pressure systems that provide a constant volume of airflow to a single zone controlled by a single thermostat. Since they do not include controls for multiple zones, this type of rooftop unit is best suited for use in the areas with fairly uniform heating and cooling loads.

The VAV configuration is gaining popularity, primarily as a result of its ability to serve multiple areas, each with different heating and cooling loads. The typical VAV rooftop unit supplies air at a constant temperature to a distribution system that includes VAV boxes to regulate airflow into each different area. The VAV configuration makes the units more flexible while improving their operating efficiency.

Rooftop units are available today in a wide range of capacities and configurations. The most common cooling configuration uses a DX system, with air or water cooling. Operating efficiencies for air-cooled units range between 1.0 and 1.5 kW per ton, and between 0.80 and 1.0 kW per ton for water-cooled units, including all fan and pump energy use. Units can also be configured to use externally generated chilled water. Today’s typical rooftop unit is 30 percent more efficient than those of earlier generations.

Rooftop units can use hot water, steam, natural gas or propane for heating, with capacities ranging from 40,000 to more than 2 million Btu for natural gas and propane units, and up to 4 million Btu for steam units.

Some of the most common complaints about rooftop units have come from maintenance personnel. Early generation systems simply were not easy to maintain. Access panels were held in place with sheet metal screws. Panels often were not replaced properly and screws were lost, exposing the interior of the unit to the elements. With time, the protective finishes on the exposed panels broke down, resulting in rusting and further exposure of unit components to the elements. Removable panels were often dropped during removal or reinstallation, resulting in damage to the building’s roof. But perhaps the most serious drawback was that the units were not designed to make maintenance easy. As a result, proper maintenance was rarely performed.

New rooftop unit designs facilitate maintenance. Exterior panels are protected by an epoxy finish that resists the elements, practically eliminating rusting problems. Machine screws have been replaced with hinged panels and latches, allowing easier access and more secure fastening of panels. Electronic diagnostic panels have been included in some system designs to ease system setup and troubleshooting. The net result is that rooftop systems offer the same advantages as earlier generation systems — including low first costs, factory assembly and ease of installation — without sacrificing performance or efficiency.

Rooftop units are suited for use in practically any low-rise application, such as in retail and institutional facilities. They are particularly well suited for applications where flexibility is required, such as frequent reconfiguration of interior spaces and functions.

Honeywell Micro Air Vehicle - Courtesy of DtiCorp.com

Honeywell Micro Air Vehicle - Courtesy of DtiCorp.com

A flying spy drone may soon join the ranks of Miami's finest, pending FAA approval of the 14-pound bot. "Our intentions are to use it only in tactical situations as an extra set of eyes," says a department spokesman. The US military has been using spy drones for years, reports Reuters, and police departments around the country are interested in pressing them into service.

The US border patrol has also been using drones to patrol the Mexican border since 2006. The FAA has been slow in allowing the drones in settled areas, however. "You don't want one of these coming down on grandma's windshield when she's on her way to the grocery store," says an FAA expert on unmanned aerial systems.

Source: http://www.newser.com/story/22591/miami-hopes-to-patrol-streets-with-flying-spy-drones.html

Fresh Look At Ductless HVAC Systems

While many types of HVAC systems are advancing, some advances are overlooked because they have occurred in some of the less glamorous types of HVAC systems: rooftop units, split ductless systems and portable AC units. The result of these gains is that facility executives have more options today when it comes to selecting systems and components to meet building needs. But having more options is good only if the most appropriate option is selected for a particular application. Simply rushing into using new HVAC technology without first understanding the appropriateness of that technology for a given application is a recipe for disaster. Inappropriate system selection can result in poor IAQ, poor system performance, high energy use, increased user complaints and maintenance headaches.

Ductless HVAC Systems

Ductless HVAC systems, like rooftop systems, have been widely promoted by some for their low first costs and their ability to provide a quick and easy solution to building HVAC problems. And like rooftop units, they have been widely criticized by maintenance personnel as being difficult to maintain. Ductless HVAC systems, like all other HVAC systems, have their applications and their limitations. Properly applied, they can provide flexibility and improve comfort in a cost-effective way. Improperly applied, they can cause maintenance headaches, contribute to IAQ problems and cause comfort problems for building occupants.

Ductless HVAC systems come in a number of different configurations. Most are two- or four-pipe fan coil units that can provide both heating and cooling. More recently, units have been introduced that are essentially ductless heat pumps, with one portion of the unit mounted in the conditioned space, and the other mounted outside the facility.

The systems offer several advantages that go beyond low first costs. With no central air handler, less mechanical equipment space is required. Lower ceilings can be used since the units require no ductwork. With individual thermostats controlling each unit, spaces can be easily zoned. With all operating components, such as the fan, the thermostat, and the heating and cooling coils located in a single unit, modifications can be readily made to the HVAC system to match changes made in space configuration or use. For these reasons, split ductless systems are frequently found in educational and healthcare facilities, computer rooms, lobbies and building entryways.

The biggest drawback of ductless systems is their inability to supply the occupied space with fresh air. Some fan coil system designs did include a small outdoor air intake, but ongoing problems with the freezing of coils led many maintenance departments to block off these intakes. Split ductless systems do not supply the conditioned space with fresh air. Fresh air to these areas must be provided by a separate system.

Maintenance requirements are an important issue with ductless systems. Because the systems are so simple in their design, and the components so relatively small, maintenance requirements can easily be overlooked. But in spite of their simple design, ductless systems require regular maintenance. Filters must be changed. Condensate pans must be checked and cleaned. Fans and belts must be inspected. Controls must be tested. The problem for many maintenance managers is that the cost of performing the required maintenance may offset any cost advantage offered by the system. But overlooking the maintenance requirements will decrease system performance, shorten equipment life and adversely impact indoor air quality.

Nevertheless, there are good applications for ductless HVAC systems. Because each ductless unit is controlled by its own thermostat, conventional fan-coil-based ductless systems provide an unlimited level of zone control, ideal for applications where individual room control is required. Split ductless systems are also suitable for meeting the HVAC needs of spaces having unusually high cooling loads, such as rooms housing telecommunications or computer equipment.

10 New Honeywell V5013 Mixing And Diverting Valves From DtiCorp.com

Fort Lauderdale, FL – Popular Honeywell online retailer DtiCorp.com (http://www.DtiCorp.com) is introducing 10 brand new Honeywell V5013 Mixing And Diverting Valves. The V5013 is a three-way valve for control of hot water, cold water, and glycol solutions (up to 50% concentration) in heating or cooling applications. These valves are used in two-position or modulating control systems. They can be used for mixing service (V5013B and F) to direct flow from one of two inlets to a common outlet or for diverting service (V5013C) to direct flow from a common inlet to one of two outlets. Mixing and diverting valves are not interchangeable.

It is important to understand the differences between mixing valves (V5013B,F) and diverting valves (V5013C). When applied to valves, the terms mixing and diverting do not always carry the same connotation as when applied to applications. Namely, a mixing application does not always use a mixing valve. The type of valve used is dependent upon the piping of the application. A mixing valve receives input flow at two ports, and discharges the mixed flow at the third port. A diverting valve receives input flow at one port, and diverts the flow to one of two output ports.

The terms diverting application and mixing application do not always clearly define the appropriate V5013. The proper V5013 depends on the valve piping. One example of this is the coil bypass application. A diverting valve installed upstream of the coil determines the flow through the coil. This is functionally the same as a mixing valve installed downstream of the coil directing water from either the coil or the bypass to the return piping. Almost all new installations can use a V5013B,F Mixing Valve, given an appropriate mixing valve piping arrangement. It is important to check the valve stem to see that it operates freely. Impaired valve stem operation may indicate that the body was twisted by faulty piping or the stem was bent by rough handling. Either of these conditions may warrant replacement of the valve body or other components. The valve should be checked at regular intervals for leakage around the packing. The packing is spring-loaded and should seldom require attention. If leakage is discovered and inspection shows that the packing gland is screwed down tightly, the valve must be repacked.

Features:

- Mixing or diverting models.

- Bronze body with threaded connections or cast iron body with flanged-end connections.

- Stainless steel stem and replaceable seats.

- Spring-loaded, self-adjusting packing.

- Constant total flow throughout full stem travel.


- Linear flow characteristic for each port, providing constant total flow control of water or glycol solutions (up to 50% concentration).

- Suitable for pneumatic or electric/electronic actuation.

- Repacking kits available for field servicing.

Product Specifications:

- Flow Characteristics: Linear, constant total flow throughout full plug travel.

- Maximum Pressure Differential:

- Two-position service: 50 psi (345 kPa).

- Modulating service: 25 psi (172 kPa).

- Quiet Water service: 20 psi (138 kPa).

- Stem Travel:

- 1/2- to 3-in. Valves: 3/4 in. (19 mm).

- 4-, 5-, and 6-in. Valves: 1-1/2 in. (38 mm).

- Body:

- Threaded Valves: Bronze.

- Flanged Valves: Cast iron.

- Stem: Stainless steel.

- Packing:

- V5013B &C: Teflon cone for ANSI Class 125 flanged valves.

- V5013F: Rubber or teflon/rubber for ANSI Class 150 threaded valves.

- Disc and Plug:

- V5013B, C: Bronze-skirted plug.

- V5013F: Linear contour plug, one piece brass construction for metal-to-metal seating.

- Seat:

- V5013B: Bronze, removable cage type.

- V5013F: Integral brass.

- Repack Kits:

- 14003294-004 TRADELINE Kit for 1/2 in., 3/4 in., 1 in. and 1-1/4 in. threaded V5013A,F Valves.

- 14003295-004 For 1-1/2 in., 2 in. threaded V5013A,F and 2-1/2 in. and 3 in. flanged V5013B Valves.

- 14003296-002 For 4 in., 5 in., and 6 in. flanged V5013B,C Valves.

- 14000501-001 Valve Bonnet Extension Kit. Further separates the actuator from the valve body for hightemperature applications.

Models available:

1) V5013B1003 Three-way, Globe, 2 1/2 in, Flanged, 63 Cv, Water or Glycol

2) V5013B1011 Three-way, Globe, 3 in, Flanged, 100 Cv, Water or Glycol

3) V5013B1029 Three-way, Globe, 4 in, Flanged, 160 Cv, Water or Glycol

4) V5013B1037 Three-way, Globe, 5 in, Flanged, 250 Cv, Water or Glycol

5) V5013B1045 Three-way, Globe, 6 in, Flanged, 360 Cv, Water or Glycol

6) V5013C1001 Three-way, Globe, 2 1/2 in, Flanged, 63 Cv, Water or Glycol

7) V5013C1019 Three-way, Globe, 3 in, Flanged, 100 Cv, Water or Glycol

8) V5013C1027 Three-way, Globe, 4 in, Flanged, 160 Cv, Water or Glycol

9) V5013C1035 Three-way, Globe, 5 in, Flanged, 250 Cv, Water or Glycol

10) V5013C1043 Three-way, Globe, 6 in, Flanged, 360 Cv, Water or Glycol

About Us: DtiCorp.Com (http://www.DtiCorp.com) carries more than 35,000 HVAC products, including industrial, commercial and residential parts and equipment from Honeywell, Johnson Contols, Robertshaw, Jandy, Grundfos, Armstrong and more. Our online catalog is easy to navigate and search, and all products have a picture and a description. If a customer has any questions about a product, they can call 800-757-5999 and speak with one of our product experts. Our mission is to offer the best prices anywhere to our customers.

Julian Arhire

Manager DtiCorp.com

Phone: 954.484.2929

Fax: 954.484.5155

Web: http://www.DtiCorp.com

###

An Energy Upgrade Can Do More Than Just Trim Energy Costs

An energy upgrade can do more than just trim energy costs. It can help boost productivity, reduce maintenance costs and improve overall facility performance. But success is far from assured. When planning and carrying out an energy project, the facility executive must avoid common pitfalls that can doom a project before it even gets under way.

Before doing anything else, the facility executive should understand the financial aspects of the project. Most finance departments view the facility group as spenders of money rather than producers of money. An energy upgrade project can reverse that perception. Seize the opportunity to communicate the idea to the chief financial executive.

First, determine if the contemplated project is being done on a “capital” or “performance” basis. A capital project entails spending company money and needs to be budgeted accordingly. Myriad financial hurdles need to be analyzed, including costs, benefits and return on investment. Will the project involve spending company cash or will some or all portions of the project be financed? If the latter, will it be traditional financing, a capital lease or an operating lease?

The facility executive should work closely with the organization’s financial group as the project is planned. That way, the facility executive is part of a team as the financing rationale is being formulated by the accounting department.

The facility executive can expect such comments as, “Why do we have to fix or replace the lights, boiler, or HVAC systems, etc.? They work just fine.” The reason is that the project will improve the bottom line and create positive cash flow with solid return on investment. Before saying this, however, the facility executive should be well aware of the financial hurdles and return-on-investment marks that the financial officer will be using to analyze the project.

The second financing model, being used more and more in recent years, is the performance-based energy upgrade project. In that approach, the contractor or energy service company (ESCO) is compensated based on performance (with performance being measured as energy and savings), in some cases guaranteeing that energy savings will result from the upgrade initiative. These guaranteed savings are then used to pay all project costs. Generally, these projects require a long-term service agreement with the contractor to be put in place, with the guarantee validated from year to year.

Performance-based financing mechanisms can take several forms. The project capitalization value can be either on balance sheet or off balance sheet.

Of course, in a performance-based upgrade with guaranteed savings, the contractor or ESCO will charge for taking on the risk that savings will not be as high as anticipated and will have its own overhead and margins to cover. As a result, projects of this nature will generally cost more over the long term than traditional capital projects; that is, the contractor or ESCO will keep a portion of the energy savings to cover those costs, as well as the costs of planning the upgrade and installing the new equipment. A company that can fund an upgrade itself will maximize savings; if funds are available, that’s clearly the best choice. Nevertheless, a performance-based approach is often a very effective way to get energy upgrades accomplished.

There are four basic kinds of performance contractors or ESCOs: those tied to utilities, equipment vendors, mechanical and electrical contractors, or independent engineering firms (consulting/developer based). Performance contracting is a highly competitive arena with marketing sizzle and aggressive savings offerings as the norm. A performance contract can serve an organization very well if critical details in contract negotiation and financing are handled carefully.

Of course, financing is only one element that has to be considered in planning. A good project plan includes a clear statement of vision, goals, objectives and methodology, along with a simple cost-benefit schedule that describes how much money will be spent and what benefits will be achieved.

Inviting Help

Initially, the plan should be packaged as an executive-summary type report for presentation to the financial group. By labeling the first version of the plan a draft, the facility executive invites the finance department to help shape the project — a good way to build an alliance and gain buy-in before requesting formal project approval and financing.

A clear, concise plan, approximately three pages, will illustrate and highlight the financial return or savings associated to the project. In the first version, don’t include any cost-benefit analysis or return-on-investment schedules — the idea is to solicit help from the financial officer in this process and, in the best scenario, get his or her help with the project.

Because the goal is to present energy savings as revenue rather than expense, be sure to capture operational savings beyond energy costs. The project will have an operations budget that will likely be established from a previous year’s expenditure; from the perspective of a financial officer, that baseline operational budget is somewhat fixed or a given. If the facility executive can show that an upgrade will reduce this baseline operational budget, the financial reality is that the savings will go directly to the bottom line or will minimally go into an “other income” category on the balance sheet.

The secret is to not give away all of the potential savings: Some should be reserved or scheduled into an incentive or reserve fund to be used for other project initiatives that may not necessarily reduce energy costs, but may improve the business environment or facility portfolio.

There’s another reason not to build the maximum proposal savings into a proposal: Projects rarely achieve the greatest savings that seem possible on paper. If the facility executive promises that maximum level of savings — and the financial officer builds it into the budget — any shortfall could make the project a failure from a financial perspective, no matter how much money it actually saves. And the financial department will be skeptical of future proposals for energy upgrades; that will help build a bridge between the facility and finance departments, not a wall. Far better to be conservative in estimating savings, and look like a hero if the project actually does better than budgeted.

In discussions about the financial justification for an energy project, it’s important to keep life-cycle costs in a prominent place on the agenda. Many times, a good project is turned down because the financial study is based solely on first cost rather than long-term costs, including operations and maintenance expenses.

Often, a higher first cost will result in lower operating and maintenance expenses; the added expense is recouped over a very short period of time when the cost of operations and maintenance is factored in. This analysis is very easy to assemble; most equipment vendors and contractors are able to produce it.

When doing performance-based energy upgrades, the contractor will most likely promote a more efficient system that may have a higher first cost because of superior return on investment and cash flow impact. An energy project analysis that does not study the long-term operating and maintenance aspects of the improvement may very well leave money on the table. It makes good business sense to look at the project both ways, even if the final decision is to go with lower initial cost.

Because energy upgrade projects don’t happen often, it is worthwhile to consider getting an experienced outside firm involved.

A long-term perspective is also important in preparing an upgrade strategy to present to the finance department. A long-term outlook might help prevent this all-too-familiar refrain: “I did a large lighting retrofit project last year that produced great results — now if I could only get management to approve fixing my boilers, chillers, HVAC or control problems. I wish they had returns like the lighting project.”

Many energy upgrade projects focus strictly on lighting. While this approach certainly will result in a winning project, many times a great opportunity is lost because the lighting initiative isn’t integrated with other energy upgrade projects. The facility executive should consider bundling the lighting upgrade with other measures and build a larger project.

One reason this integrated approach isn’t taken, say many facility executives, is that management won’t approve more money for the other projects. But companies are sometimes willing to expand the budget if a good plan is presented with the budget ramifications for bundling, or if both a capital and performance-based budget are presented. Facility executives who do lighting work as a stand alone and then undertake other energy upgrades afterwards risk being seen by the financial side of the organization as a constant drain on capital reserves or budgets.

Control and Monitoring

When energy upgrades are not monitored and tracked, the initial savings often dwindle over time. In most cases, it’s a combination of small things: temperature set points that are overridden and never reset, or lights that are left on longer. But whatever the causes, the end results are too often the same: The absence of a verification mechanism and lack of interest in validating economies means that costs creep up.

The control and automation system in place is the most effective process for validating and monitoring performance. But that system has an even more important role: turning things off.

In simple terms, a control system comprises two types of points. Monitoring points — inputs — supply critical information regarding status and values associated with measurements; control points — outputs — signal the on-off mechanism of devices. The best way to save energy is to turn things off: shutting off lights when no one is in the room, for example, or turning air handling equipment off at proper times. While there will always be more inputs than outputs, it is important to make sure that there are enough outputs. As a rule of thumb, if less than 25 percent of the points are outputs, it’s worth taking a close look at the whole proposal to assure that it is really capable of producing significant savings.

Reshaping Perceptions

A successful energy upgrade project can bring benefits beyond energy savings. One of those benefits can be a change in the way the facility department is perceived by top management.

More and more, the facility department is expected to be a business unit as opposed to a service unit. That seems completely appropriate, given the range of contributions the facility can make to the bottom line. No matter what the title, the time has clearly come for the facility executive to be part of the top management team. But the facility executive has to take the initiative. An energy upgrade is a good place to start.

Julian Arhire is a Manager with http://DtiCorp.com – http://DtiCorp.com carries more than 35,000 HVAC products, including industrial, commercial and residential parts and equipment from Honeywell, Johnson Contols, Robertshaw, Jandy, Grundfos, Armstrong and more.

DtiCorp.com is Introducing the New Honeywell PP905B1008 Static Pressure Sensor

Fort Lauderdale, FL – Popular Honeywell online retailer DtiCorp.com (http://www.DtiCorp.com) is introducing the brand new Honeywell PP905B1008 static pressure sensor. One-pipe, direct-or reverse-acting pressure sensor used with RP908/RP920 Controllers to provide control of duct static, velocity, or differential pressure in airflow applications. Replacement devices available for Johnson, Powers, Robertshaw, Barber-Colman, and older Honeywell devices.

Features:

- Three-diaphragm design minimizes calibration shift with static pressure changes in velocity pressure applications.

- Not sensitive to normal supply air variations.

- Continuous static, total, velocity, or differential pressure indication available by using differential pressure gage.

Specifications:

- Description: Static Pressure Sensor used with RP920/RP908

- Application Type: Static Pressure

- Pressure Range (psi): 2 in. wc

- Pressure Range (kPa): 0.5 kPa

- Maximum Safe Operating Pressure (psi): 25 psi

- Maximum Safe Operating Pressure (kPa): 172 kPa

- Output Pressure Range (psi): 3 psi to 15 psi

- Output Pressure Range (kPa): 21 kPa to 103 kPa

- Connections: Push-on barb for 1/4 in (6 mm) Diameter tubing

- Temperature Range (F): 40 F to 120 F

- Temperature Range (C): 4 C to 50 C

- Setpoint Range (in. wc): 0 in. wc. to 7 in. wc. (Adjustable)

- Setpoint Range (kPa): 0 kPa to 1.7 kPa (Adjustable)

- Mounting: Duct mount

- Dimensions (in.): 8 in high, 9 in wide, 4 1/8 in deep

- Dimensions (mm): 203 mm high, 228 mm wide, 105 mm deep

- Airflow Usage: 0.021 cfm (9.9 ml/s)

- Action: Can be set for Direct Acting or Reverse Acting

- Mainline Air Pressure (max.) (psi): 25 psi

- Mainline Air Pressure (max.) (kPa): 175 kPa

- Mainline Air Pressure (min.) (kPa): 112 kPa

- Span (Non-Adjustable) (in. wc): 2 in. wc.

- Span (Non-Adjustable) (kPa): 0.5 kPa

- Mainline Air Pressure (min) (psi): 16 psi

- Maximum Safe Static Pressure (in. wc): 28 in. wc

- Maximum Safe Static Pressure (kPa): 7 kPa

- Comments: The setpoint determines the midpoint of the span.

About Us: DtiCorp.Com (http://www.DtiCorp.com) carries more than 35,000 HVAC products, including industrial, commercial and residential parts and equipment from Honeywell, Johnson Contols, Robertshaw, Jandy, Grundfos, Armstrong and more. Our online catalog is easy to navigate and search, and all products have a picture and a description. If a customer has any questions about a product, they can call 800-757-5999 and speak with one of our product experts. Our mission is to offer the best prices anywhere to our customers.

Julian Arhire

Manager DtiCorp.com

Phone: 954.484.2929

Fax: 954.484.5155

Web: http://www.DtiCorp.com

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Five Factors To Energy Efficiency

One of the most popular ways of improving building energy efficiency today is through a lighting systems upgrade. New, energy-efficient lighting systems offer the potential of reducing lighting energy requirements by 35 to 50 percent, with additional savings being realized in reduced air conditioning costs as lower lighting system energy use translates into reduced cooling loads.

When considering energy-efficient lighting systems, facility executives can select from a wide range of options, including fluorescent lamps, compact fluorescent lamps, electronic ballasts, efficient fixture designs and automatic lighting controls. While each of these components is important to the overall operating efficiency of the system, none is more important than the ballast selected. Selecting the proper ballast can make the difference between a lighting system that is simply more efficient than the one it replaced, or one that is highly energy efficient.

All lighting system upgrades today involve replacement of the ballasts. In most cases, the upgrade involves moving from the older magnetic ballast to one of the newer electronic ballasts. Electronic ballasts offer improved operating efficiency over magnetic ballasts, reducing ballast energy requirements by an average of 35 percent. But not all electronic ballasts are created equal. Manufacturers have developed a number of different ballast designs with different characteristics for use in different applications. There are five major ways in which ballast selection will impact the energy performance of the lighting system. To achieve optimal performance from the new lighting system, ballasts must be carefully selected to match the needs of the space.

1. Electronic Ballast Efficiency
   
   Simply stated, electronic ballasts are significantly more energy efficient than their magnetic counterparts. As a result, the manufacture of magnetic ballasts will most likely be curtailed for general purpose lighting applications.The improvement in energy efficiency achieved by electronic ballasts comes as a result of several factors, including lower internal losses and higher operating frequencies. Magnetic ballasts suffer from core losses that are inherent in the design and operation of the ballast. Electronic ballasts operate without the need for windings and magnetic fields, thus eliminating magnetic losses completely.
   
   
   

   Electronic ballasts also operate at a higher frequency than magnetic ballasts. Magnetic ballasts operate at line frequency, 60 Hz. This means that the arc that excites the phosphors on the inside surface of the fluorescent tube is triggered 60 times each second. Electronic ballasts operate at frequencies ranging from 20 to 60 kHz. At these higher operating frequencies, the arc excites the phosphors for a longer period of time, resulting in the generation of 10 to 15 percent more light for the same energy use.

   
   

   Operating at a higher frequency also eliminates one of the most common complaints associated with fluorescent lamps: flicker. With the arc being triggered at 60 times per second with magnetic ballasts, some people can detect a flicker in the light output of the lamps. Electronic ballasts, with their higher operating frequency, completely eliminate this flicker. While the lamps are still switching on and off with the arc, the higher operating frequency makes it impossible for the eye to detect.

   
   


2. Ballast Factor
   
   
   One of the most frequently overlooked yet important items when selecting lighting system components is the ballast factor. The ballast factor is a measurement that rates the relative light output of a ballast with respect to the light output of the same lamp operated by a reference ballast. The higher the ballast factor, the higher the light output of the lamps. The lower the ballast factor, the lower the light output of the lamp and the lower the energy use of the system. The ballast factor is dependent on both the ballast selected and the lamp installed.The ballast factor of the units selected for a particular installation will significantly impact the total light output and energy use of the lighting system. While magnetic ballasts were available in a narrow range of ballast factors, between 0.925 and 0.975, electronic ballasts are available in a wide range of ballast factors — from as low as 0.73 to as high as 1.2. This allows facility executives to select ballasts that provide a wide range of light output.
   
   
   

   Consider a lighting system upgrade where fixtures with magnetic ballasts and T-12 lamps are replaced on a one-for-one basis. If the lighting levels in the existing system were adequate, simply replacing the fixtures with ones using electronic ballasts with a ballast factor of 1.0 and T-8 lamps would reduce energy use, but it would result in an increase in lighting levels. Selecting a ballast with a ballast factor of 0.88 would reduce lighting system energy use even further while maintaining the original lighting levels within the space. A higher ballast factor would increase overall lighting levels, while a lower ballast factor would reduce lighting levels and energy use.

   
   

   It should be noted that ballast factor can impact lamp life. High ballast factors generally shorten lamp life and accelerate lamp lumen depreciation. In system designs, these factors must be evaluated against the cost of having to alter the layout of the lighting fixtures.

   
   

   By selecting a ballast with the proper ballast factor rating for the lamps that will be used allows facility executives to control both light output and lighting system energy use.

   
   


3. Dimming
   
   With magnetic ballasts, dimming was an option, but it was not cost effective in most applications. Dimming controllers for magnetic ballasts were bulky, expensive and not very effective. Most systems could not reduce light output much below 50 percent of full brightness. Dimming tended to increase the problems associated with lamp flicker. Many systems required lamps to be started at full brightness, then dimmed to the desired level. As a result, most applications that required dimming yet wanted the efficiency of fluorescent lamp operation installed two separate lighting systems — one fluorescent and one incandescent.Dimming electronic ballasts have eliminated the problems associated with trying to dim magnetic ballasts. Controllers are small and inexpensive. Light output can be controlled to as low as 5 or 10 percent of full brightness. Flicker at low light levels is eliminated due to the high operating frequency of the ballasts. Costing approximately 35 to 50 percent more than conventional electronic ballasts, this new generation of electronic ballasts has made fluorescent lamp dimming practical, efficient and affordable.
   
   
   

   Most dimming electronic ballasts are controlled by a 0-10 volt DC signal from the controller. Some models make use of AC line-phase controller signals, eliminating the need for special control wiring.

   
   

   Dimming electronic ballasts can be used in any application where dimming is desirable, such as in meeting rooms. While use of dimming ballasts in these applications will save energy by eliminating the need for a separate incandescent system, the real potential for energy savings comes from applications that can make use of natural light.

   
   
   

   In spaces with even moderate areas of exterior glass, natural light is available for use in lighting the space. To be used effectively though, there must be a way to automatically sense the total light level in the space and adjust the light output of the fluorescent fixtures as the amount of natural light varies. Dimming electronic ballasts give facility executives that capability.

   
   

   The typical dimming system uses a sensor to measure the overall lighting level in the space. The sensor, connected to the dimming controller, regulates the light output of the fluorescent fixtures to keep the total light levels constant. A single controller can be connected to all dimming ballasts, or multiple controllers can be connected to individual banks of ballasts based on their distance from the glass. The result will be a decrease in lighting energy requirements of 35 to 75 percent for the typical office application.

   
   


4. Rapid-Start vs. Instant-Start
   
   Electronic ballasts, like the older magnetic ballasts, are available in two basic types: rapid-start and instant-start. Selection of the ballast type impacts overall energy use because of differences in the operation of the ballasts.All fluorescent lamps need a means of starting the lamps as well as regulating their operation once started. Rapid-start lamps have two circuits. One circuit controls normal operation of the lamp, and the second provides a low voltage to the lamp’s electrodes. This low voltage heats the electrodes to between 70 and 100 degrees Celsius in a few seconds, allowing the lamp to light. Once lit, most rapid-start ballasts continue to supply the voltage to the electrodes, resulting in an energy use of two to three watts per 40 watt lamp.
   
   
   

   Instant-start ballasts do not heat the lamp’s electrodes to start them. Instead, they temporarily apply a high voltage to the lamp that strikes the arc. Once the lamp is lit, the high voltage is turned off. As a result, energy requirements are reduced. This improvement in energy performance comes with a penalty. The use of high voltage to start the arc accelerates erosion of the emissive coating on the lamp’s cathode, decreasing lamp life. Compared to rapid-start ballasts, instant-start ballasts have a lamp life that is approximately 25 percent shorter. The more frequently the lamp is started, the shorter the lamp life.

   
   

   The decision to use a rapid-start or instant-start ballast is usually made based on the application. Applications that are switched more frequently, such as those in areas controlled by occupancy sensors, are better suited for rapid-start ballasts. Applications where lights burn for longer times per start can benefit from the energy savings produced by instant-start ballasts, without significantly reducing relamping intervals.

   
   

   A third type of electronic ballast is becoming more common: the programmed-start ballast. Programmed-start ballasts offer the energy efficiency of instant-start ballasts without sacrificing lamp life.

   
   

   Programmed-start ballasts apply a low voltage to the lamp’s electrodes for starting, like instant-start ballasts. Unlike instant-start ballasts, programmed-start ballasts turn off that voltage once the lamp is lit. By turning off the voltage, these ballasts achieve the energy efficiency of instant-start ballasts, while providing the lamp life of rapid-start ballasts. While programmed-start ballasts are relatively new, they are projected to replace most rapid-start units.

   
   
   


5. Power Factor
   
   Power factor is the ratio of active power in a circuit to apparent power. In purely resistive loads, the power factor in the circuit is 1.0. But as electrical loads are added to the circuit that are inductive, such as those from induction motors and ballasts, there is a phase shift in the circuit between the current and the voltage, and the power factor decreases. In most commercial and institutional facilities, the overall power factor is typically between 0.85 and 0.97. In industrial applications, particularly those having a large number of induction motors, it can fall to 0.75 or lower.Power factor impacts the current-carrying capacity of a circuit and the cost of electricity. Depending on the rate structure in effect for the facility, low power factor can carry a significant penalty, costing facilities thousands of dollars each month.
   
   
   

   Power factor is important when considering electronic ballasts because they can cause reductions in overall power factor by distorting the current wave shape. These distortions are measured by the unit’s total harmonic distortion (THD). The higher the THD, the greater the ballast’s impact on power factor. Correcting this distortion is difficult and expensive. Although the load drawn by a single electronic ballast is very low, given the number of ballasts that may be installed in a particular facility, their overall impact on system power factor can be significant and costly.

   
   

   Electronic ballasts that limit THD and therefore the impact on power factor tend to cost more than those with a higher THD, but their additional first costs can be quickly recovered, particularly in applications with a high-cost penalty for low power factor and a high lighting load. High THD generated by electronic ballasts and other sources can also cause problems within other electrical equipment in the facilities, such as the overheating of induction motors and interference in office equipment.

   
   

   For most applications, limiting electronic ballast THD to values of less than 20 percent will avoid problems with other equipment and low power factor. Electronic ballasts are available with THD ratings of below 10 percent for specialized applications.