Bridgeport Microgrid

Bridgeport Microgrid is a partnership between OR&L Construction in Branford, Controlled Air and Power Island Energy in Jacksonville, Fla.

Controlled Air, Inc. will be in charge of the design build concept. This includes the design and installation of the Congeneration System, chilled water system, controls system, underground piping, and thermal loop for both chilled and hot water.

A microgrid is a power system designed to provide power to buildings continuously, even in times of natural disasters or when the main electrical grid fails.
The project is part of a municipal pilot program launched through the state Department of Energy and Environmental Protection in 2013.

In addition to providing power to key municipal buildings, Bridgeport’s system will use the generators’ excess heat to provide heating and cooling to City Hall, police headquarters and the nearby Cabaret building.
According to DEEP, Bridgeport microgrid will own the generation for the city’s microgrid.

The microgrid is expected to be operational by July 2017.

Update on R-22 Replacements

R-22 Replacements

R22 Replacement – As we had previously reported, the price of R22 continues to rise. Since the start of the summer season, we’ve seen the wholesale price of R22 jump over 25%. If you have spent any time researching this subject on the internet, you’ve seen the numerous manufacturers of refrigerant who promise a seamless replacement while improving the efficiency of the unit. While at the same time research any of the HVAC bulletin boards and you’ll find horror stories from service technicians trying to utilize these replacement refrigerants. All of this contradicting information makes you wonder if R22 can be replaced?
When Controlled Air, Inc. started our search for a quality replacement, we looked for key areas of importance:

  • Price
  • Availability
  • Global Warming Potential
  • Ozone Depletion Potential
  • Flammability
  • Toxicity
  • Oil capability
  • Capacity to R22
  • Technical support
  • 3rd party/real world testing

The good news is we are finding alternate refrigerants that are reasonably priced and work well as a drop in replacement. In particular, we’ve have had success with R422B. Though we have not tested this refrigerant in all applications, we feel strong enough to offer it for most standard HVAC applications without worries. For other applications, we’ll work closer with the manufacturer to see what changes are needed to either make R422B work or try another refrigerant. There still may be configurations where the only option will be R22 but in most cases R422B may the key to extending the life of your R22 equipment.

Heat Exchangers

Cooler weather is quickly approaching. With the hot summer we had, the last thing we might think about is the heating components of our HVAC system. In a rooftop unit or furnace, the transfer of heat from the direct fire to the air flowing into the space is the job of the heat exchanger. The heat exchanger is critical to proper heating and as such, should be inspected annually to avoid unforeseen problems.

In a rooftop unit, the heat exchanger has been exposed to condensation all summer because it is positioned after the cooling coil and the interior of it is exposed to the outdoor humidity. The humidity will condense on the inside and will over time cause rust to form. This rust will cause the heat exchanger to crack and allow an opening between the fire and air side of the exchanger. Under the right conditions carbon monoxide may enter the airstream into the building.

In most cases, we find the crack in the exchanger allows system air to flow into the fire chamber due to the positive pressure from the system fan. This air flow tends to impinge or distort the flame on the burner and blow the fumes into the unit cabinet. In a worse case scenario, the system air will cause the flame on the burner to roll out of the exchanger into the compartment of the unit.

It is important to be aware that when a contractor finds a bad heat exchanger that could cause harm, injury, fire, or damage to property, technicians are instructed to shut off the equipment. If inspected by a utility company, they will red-tag the equipment and lock off the gas supply.

Maintenance for a heat exchanger is an inspection only as there is little that can be done to stop the condensation and decaying process. Proper heat exchanger performance also ensures that the unit operates at its peak efficiency. A yearly inspection service will look for cracks, plugged or blocked passages, and proper flame color, size or appearance across or out of the burner.

Webster Bank Arena

Arena 3

At the Webster Bank Arena, Controlled Air, Inc. replaced two boilers which had a gross output of 4,334 MBH and an operating efficiency of 79% with two new high efficiency Sonic SC-4000 Patterson-Kelley boilers. The Sonic 4000 boiler has a gross output of 3,840 MBH and an AHRI thermal efficiency of 96.0%.

Carrier’s Hourly Analysis Program (HAP) was used to provide energy calculations and comparisons. The analysis was performed by first constructing the baseline.  From the output of the building simulation, calculations showed that by implementing the proposed Patterson-Kelly efficiency boilers, an annual savings of 19,139 CCF was projected when compared to the ASHRAE code minimum 82% efficient boilers. At the calculated average utility rate of $1.2567[1] per CCF, this would amount to approximately $24,051 in savings annually.

When the project was completed, they received a $64,418 incentive for the boiler upgrade. 

If it is time to upgrade your equipment contact us to find out how to improve efficiency and save money on your utilities!


Greenhouse Gas Emissions Savings

Controlled-Air-2015Controlled Air, Inc, is an active member of CHP EPA Partnership. Each year we submit information about the CHP/Cogeneration project that we complete. In 2015 our six CHP projects have avoided emissions of an estimated 5,720 metric tons of carbon dioxide, compared to conventional energy sources. This includes 2015 avoided emissions of more than 1,490 metric tons, equal to that from the generation of electricity used annually by 205 homes.

We exceeded 2014’s figures by 1,500 metric tons!

The Final Phaseout of R-22

r22-phaseoutThe final phase-out of R-22 will once again be impacting supplies and prices of R-22.

The U.S. Environmental Protection Agency (EPA) final phasedown schedule is as follows:
Drop from 51 million pounds allowed in 2014 to 22 million pounds beginning Jan. 1, 2015. Subsequently, 18 million pounds of new and imported R-22 will be allowed in 2016, 13 million pounds in 2017, 9 million pounds in 2018, and 4 million pounds in 2019. No new or imported R-22 will be allowed in the U.S. on or after Jan. 1, 2020.

Industry leaders estimate the R22 aftermarket consumption for end users to be somewhere between 50 to 60 millions pounds for 2016. With only 18 millions pounds of new R22 and an estimated 8 million pound of recycled R22, there will be a supply and demand imbalance. This will drive the price of R22 up.

It’s important to have an understanding about how these changes will impact you and to have a plan on how to address these issues either before or when a major failure occurs. The first step would be to evaluate your equipment. What is the age of the equipment? Is it the type of equipment where it’s more cost effective to replace the equipment instead of repairing when there is a major component failure?

The EPA set up regulations to ban the production of heat pumps and air conditioners that contained R-22 after December 31, 2009. HVAC equipment manufacturers discovered a loophole in the law that allowed them to manufacture and sell system components as long as these components contained no refrigerant. This loophole has recently closed and dry units will no longer be available. This change will impact businesses that have smaller R22 split systems with condensing units. Condensing units have a short lifespan so when there is a major component failure in a condensing unit, it is normally more cost effective to replace the entire condensing unit. With dry units no longer available, the first option would be to use an R410A condensing unit and add an expansion valve. In some cases switching to an R410A condensing unit will require replacing the refrigerant piping due to sizing requirements and replacing the evaporator coil. In either case, repair costs and the amount of time needed to replace a condensing unit will be driven upwards.

If you have rooftop style units or larger condensing units where normal repair practices are to replace the major components upon failures, your options are to utilize a drop in replacement refrigerant when it’s time for a major repair.

There are disadvantages to using a drop-in refrigerant. When you introduce a refrigerant that the system was not built for, you can lose some efficiency. The efficiency loss can range depending on your system and the replacement refrigerant used.

Contact us today to get a estimate on what it will take to get your equipment ready for the changeover or to upgrade your system.


Legionella is an air-borne bacteria that can affect those working in close proximity with Cooling Towers, Evaporative Condensers, and Fluid Coolers, as well as those inside closed office buildings.

Cooling towers, evaporative condensers and fluid coolers use a fan to move air through a recirculated water system. This allows a considerable amount of water vapor to be introduced into the surrounding area. This water may be in the ideal temperature range for Legionnaires’ disease bacteria growth, 68°-122°F. Legionella grows easily in the water, especially if algae and scale are present. Legionella can be dispersed with aerosolized drift or with the evaporate, but it may enter the air-conditioning system if there is a break between its ducts and those of the cooling tower or evaporative condenser.

Proper maintenance can prevent the spread of this bacteria.The cleaning of cooling towers should occur quarterly. Corroded parts, such as drift eliminators, should be replaced. Algae and accumulated scale should be removed. These measures will not only control the growth of bacteria, but will also maintain operating efficiency. During cleaning operations in confined spaces, safety procedures for entry into confined spaces should be applied.

Cooling water should be treated constantly. Ideally, an automatic water treatment system that continuously controls the quality of the circulating water should be used.

Fresh air intakes should not be built close to cooling towers since contaminated aerosols may enter the ventilation system. Air filters should be examined, cleaned and/or replaced periodically and tested for leaks. Cooling towers should be positioned so the drift or evaporate does not enter the fresh air intake.  The water system should be flushed out on a regular basis to prevent the water from stagnating.

University of Bridgeport, Bates Hall VRF System

We planned, designed, managed and installed one complete Lennox VRF system at Bates Hall, a historically recognized building on the campus of University of Bridgeport. This system was chosen due to the lack of space provided and the exceptional zoning capabilities it provides the customer. This system has the ability to heat and cool at the same time at very low energy cost.

Bates Hall is the largest Lennox VRF System in New England. The VRF system includes 2 outdoor units and 18 indoor units. VRF Systems provide simultaneous heating and cooling throughout the building, as well as auxiliary heaters for negative temperatures. The VRF system further includes variable speed drives with stage up/stage down capabilities. 

IMG_5037What is VRF? 

Variable Refrigerant Flow, VRF, is a system that provides simultaneous heating and cooling by absorbing excess heat energy in one zone and transferring it to heat another. This helps you maintain the ultimate level of comfort while operating at maximum efficiency. By offering a building the ability to create localized comfort with independent temperature control, VRF can help every occupant enjoy a perfectly heated, cooled, and humidified area.  This makes customization easy and efficient. VRF is a flexible system in operation and installation. Multiple configurations of indoor units are available, including wall and floor mounts. Lennox VRF is ideal for a wide range of buildings and workplaces. Perfect applications for VRF include: Lodging, Healthcare, Multi-family structure, Hospitals, Education, Retail and Dining. It is equally suited for new building or upgrades in an existing building.

What are the Benefits?

  • 20%-25% more efficient then conventional systems: VRF systems may cost more than traditional central air systems up front, but this cost can be offset by lower energy bills and repair expenses over time.
  • Higher comfort with individual zone control: No matter how your building is used, this customizable solution allows you to control different comfort needs independently. Unused rooms’ climate controls can be switched off entirely.
  • Smaller Footprint Quiet: In a VRF system, the noisier condensing unit is typically outside, and the indoor air handlers are smaller and quieter than a traditional systems.
  • Consistent comfort: The VRF HVAC system can detect the precise requirements of each zone, and send the precise amount of refrigerant needed to do the job. As a result, each area of your space is consistently comfortable with well-controlled humidity and no hot or cold spots.
  • VRF systems take up much less space than forced-air systems—a benefit that’s especially important in existing structures.

Multiple Control Options

  • Up to 16 Zone Levels
  • Centralized level (up to 128 indoor units)
  • Integrated building level (multiple VRF systems)
  • Integrated connectivity (for control using any web-connected device)

Financing/Rebates can work with CPACE financing. VRF is so new that it doesn’t have specific tax credits and rebates but it does/can qualify for rebates and incentives with proper energy modeling.

Contact us for more information 203-481-3531

Ice Dams

What is an Ice Dam?

An ice dam is a hump of ice that forms at the edge of the roof. Ice dams form when a home’s escaping heat warms the roof and melts the underside of the snow layer on the roof. Water trickles down the roof until it reaches the cold at the edge of the roofing, where it freezes. After a while, the ice at the edge gets thicker, forming an ice dam. This puts your roof and the inside of your building at risk. If the water reservoir behind the ice dam is large enough, water can back up under the roof shingles and damage ceilings.

Stay Safe if Ice Dams Form

  1. Clear off roof hatches of snow and ice. If hatches are not cleared and there is an emergency we will not be able to access the roof.
  2. Clear snow & ice away from heat pumps. Heat pumps can freeze, causing improper functioning.
  3. If you run A/C in the winter due to internal load, be sure to:
    1. Clear snow & ice away from condensing unit.
    2. Make sure your A/C is capable of low ambient operation.
  4. Keeping snow away from equipment electrical panels will help prevent water from entering and possibly causing short circuiting.
  5. Safety with snow & ice is always a concern. Keeping your equipment accessible during the winter time can make it easier for our service technicians to access your equipment safely if repairs are necessary.
  6. Beware of snow and ice falling on family members, tenants & the public.
  7. Ice deposits can form slip hazards on the ground.
  8. Beware of mold and spores caused by moisture accumulating indoors can be hazardous to your health.

Tips to Prevent Ice Dams

The four possible solutions to reduce escaping heat and prevent ice damming are:

  1. Sealing air leaks between the warm interior and the attic or cathedral ceiling.
  2. Adding more ceiling insulation.
  3. Improving ventilation between the top of the insulation and the roof sheathing.
  4. Installing a rubberized membrane under the roofing.