Acutherm manufactures components for heating and air conditioning systems that make commercial buildings more comfortable, save energy, offer sustainability and can also reduce total installed costs. Our components are called Therma-FuserTM variable air volume (VAV) diffusers. They are used in VAV air conditioning systems which, instead of varying the temperature of the cooling air, vary the amount of the cooling air to maintain even room temperatures. We make buildings more comfortable places to work. Therma-FuserTM VAV diffusers are ceiling air diffusers with the thermostat and VAV damper built-in. These small zones of control provide individual comfort that precisely match the comfort requirements of the room or portion of the room served. Therma-Fuser diffusers also provide a constant discharge velocity with comfort benefits of higher throws, no cool air dumping, better room air movement and uniform temperature distribution. Therma-FuserTM VAV diffusers are energy efficient VAV diffusers that produce 15% to 47% energy savings.

The thermostat-actuator and damper inside each unit is designed to reduce the flow of supply air such that the volume entering the space is only the amount necessary to maintain a set temperature.  By preventing overcooling and overheating, overall energy usage is greatly reduced. Therma-FuserTM VAV diffusers also have the lowest pressure drop of any VAV terminal, allowing for low-pressure systems and low energy fan motors. No energy is required to operate the diffuser’s controls. 26 LEED® credits can be influenced by specifying an Acutherm Therma-Fuser™ system. Read more on energy studies. Achieving LEED with Therma-FuserTM Systems. Different from a fixed-grill diffuser, a Therma-Fuser™ diffuser is a self-contained zone of control with the thermostat and VAV dampers built-in. Expensive above the ceiling labor and controls are significantly reduced.  On an installed cost basis the Therma-Fuser™ diffuser provides the lowest cost per zone of control.

It is simply the most cost-effective way to manage a zone. We provide buildings with a sustainable HVAC solution. The small zones created with Therma-Fuser diffusers make office layout changes easy. No zone is split when office walls are added or moved. Customers using Therma-FuserTM VAV diffusers for as long as 30 years testify that no maintenance at all has been required. One of the reasons for this is the product’s simple construction that contains very few moving parts.central air conditioner repair ottawaMany studies have shown that energy losses in heating/cooling ducts in most homes can run 25 percent to 30 percent — or more. dx unit in hvacThe majority of these losses can be traced to air leaks in the equipment or ductwork that can easily be found and repaired. window ac unit tripping breaker

Although typical costs for remediation run $350 and up, the savings will usually be recouped within just the first year. Finding air leaks can be time-consuming, but there are some tricks that will not only speed up the job but make the inspection much more accurate. One is the use of a blower door test: A large fan at the front door will pull air out of an otherwise closed-up house, creating drafts from leaks that are much easier to detect than the typical slow infiltration of air. (The blower door also reveals any leaks in the building envelope itself.) Another tool called a duct leakage detector or a flow hood blows air into the duct system through a register after all other returns and registers have been sealed. With both tools, special instruments indicate any differences in pressure or where air leaks occur. Here's a list of what you'll need to repair such leaks in your customers' HVAC systems: battery-operated drill gun, drill bits and magnetic hex-head screwdriver bits

fool for installing duct zip ties tightly sheet metal screws (hex head) duct zip ties (for flex duct) duct mastic and brush tape mastic (aluminum tape with 15-mil butyl backing; can be used in areas up to 200 degrees F) Leaks in HVAC air handlers can usually be seen, felt and heard. Common places to find them are at ill-fitting cover panels or those with missing screws; where air-conditioning pipes enter the housing (grommets may be missing or leaky); the entrance of the attached air-filter insertion point (base); and plenum and return-air connectors. Air leaks might also occur if whole-home air filters have been improperly installed. Use this checklist to inspect and repair these energy wasters: 1. Make sure that all panels and connections are secured with screws and that all panels are in place. 2. Straighten bent panels and repair their seals. 3. Stop all leaks with liquid or tape mastic or with permagum, which stays pliable and can be removed for access later.

4. Make sure that all interior insulation is in place and tightly secured to the metal walls and panels. Unfortunately many air handlers and furnaces have air leaks all over them because of poor manufacturing practices. We cannot rebuild these in the field. They can be sealed with permagum, or with silicone for a permanent seal. For repairing simple leaks in the air ducts: 1. Make sure that all metal fittings are firmly screwed together on four sides, then covered with liquid or tape mastic, and fully re-insulated. 2. The s-cleat and drive connections on ductwork are notorious for leaking. All these should be sealed with duct sealer mastic. 3. On flex duct with no metal ends, secure the inner lining to the metal boot firmly with duct zip ties, then secure the insulation and outer wrap. Zip ties are fine for the exterior insulated wrap, but duct zip ties alone on the inner liner will not secure the duct to the slick metal fitting. Use sheet metal screws with washers at the spiral wire to prevent the inner liner from slipping off.

(Codes demand that insulated flex duct be secured with UL 181-B-FX tape.) 4. Cover all connections of accessories (such as humidifiers) with liquid or taped mastic. (Remember that many of these must be removed later for service.) Ducts are often damaged when people come in contact with them in storage areas, such as attics. Such damage can result in major or minor leaks, depending on how bad it is, and it requires a thorough inspection to find it: Metal ducts or flex ducts that aren't properly secured with screws or duct zip ties can fall apart, resulting in major air losses. Fiberglass ducts can be crushed or punctured. The outer covering of flex ducts can tear, resulting in energy losses and even an accumulation of moisture between the duct's inner and outer liners, which leads to worse problems. Any major damage may require replacement of the section of ductwork, but minor damage and rips may be sealed using 15-mil butyl tape mastic with a thick adhesive on the back.

Plenum or Mixer Box Connections: 1. Make sure that all seams are fixed tightly and screwed together (when necessary). 2. Make sure that all connecting boots are tight at the seams and sealed with liquid or tape mastic. 3. Make sure that all insulation is in place and well-secured. Air Diffuser Boxes and Grilles: 3. Make sure there are no leaks between the discharge grille facing and the space between the wall studs or ceiling joists. 4. Make sure that all non-grille surfaces are insulated. Leaks in air returns can be hard to locate because the negative pressure is difficult to both see and hear. Finding and repairing such leaks requires a close inspection. And non-ducted returns (as in spaces between wall studs or ceiling joists) are notorious for being sources of both indoor air pollutants and leaks from outside or unconditioned sources. That's why it is best to fit all air returns with a tight metal or plastic lining, or thoroughly coat them internally with mastic to cover all leak sources.

Once you've secured all connections to the ducts, as listed above, verify that all seams are tight and covered with mastic, and that there are no leaks between the return grille facing and the space between the wall studs or ceiling joists. We often find separate filter housings (such as for electronic air filters) located in unconditioned areas. Because filters are frequently changed or cleaned, they can start to leak air. Here, the use of any sort of mastic would become a hindrance to any sort of future servicing, so we recommend repairing only any damaged seals. Permagum is good for this job. It is easy to put on and easy to remove. An annual check of the customer's HVAC system will catch any new problems before they start running up energy bills and affecting indoor air quality. These inspections and repairs are a good investment in a comfortable and energy efficient home. Jim Wheeler has more than 25 years of experience in installation and repairing heating and cooling systems.