MAKE UP AIR
Over the past few years we have been building our portfolio of products to offer a full offering of high outside air make up air units of upto 100%. Starting as low as 100 cfm and legitimately up to 20,000 cfm (although higher with custom or multiple units) we can do brute force (no return connection) or energy recovery (with options). Incidentally, units can be set up for up to 100% mechanical heating and cooling (ie recirculating and increase outside air up to complete make up air).
One thing to consider: Make Up Air applications are very different from standard recirculation units as in the northeast the air entering the unit can be as low a 0F up to 100 vs 55-80. Additionally, unlike recirculating air units where the entering air is the same as the sensor (ie the t-stat is in space that you are in), the air for make up air units are not where the occupant is. Therefore, the controls must be closely looked at as simple controls may prove problematic. For example, on a 0 degree day, the unit will see 0 but the space may be 70F. If the space is satisfied you can’t turn the unit off as you will deliver freezing air into the space. You also can’t send 95F to space when it is satisfied. For cooling it gets more complicated as not only does one need to consider temperature, but humidity levels as well (see dehumidification and hot-gas reheat, etc)
Here Is A Quick Summary For Easy Reference:
- Heating Only (direct fired, indirect fired gas heat, hot water, steam, electric)
- Cooling Only or with heat
- HVAC units with energy recovery
- Energy Recovery only
- Units under 1000 cfm
- Indoor Packaged units- air source and water source
- Retrofit ideas
Heating Only 100% : Rupp offers Direct and indirect units, indoor and outdoor. Full modulation heat and industry leading lead times. Competitively priced.
Heating with Small CFM: Tutco now offers UL listed electric duct heaters which run cooler, allowing more kw/sq foot which equates to higher delta T’s
Cooling only (with heating options) : Addison offers multiple options as every application is different. We can do 100% outside air, brute force or incorporate an integral molecular sieve wheel to cut the mechanical load by upto 40%. The Unit can ship with full controls and a premium dehumidification cycle using hot-gas reheat and subcooling coil. The same packaged unit can incorporate primary heat with high turndown gas burners, hot water, steam or electric. Need an indoor solution? We can configure a United Cool Air Vertical or Horizontal unit to bring 100% outside air down to neutral air temperatures.
HVAC units with energy recovery. Again, an Addison unit can incorporate with an integral molecular sieve wheel for full Cooling, Heating and dehumidification. Need a lower dewpoint? The NovelAire DES/DX ERV utilizes the same wheel and a commercial grade desiccant wheel to provide dewpoints as low as 40. In some cases a heat pipe wraparound coil can clip 25% off the load by using the sensible heat of the outdoor air as reheat as shown here. (this concept can be used for retrofit applications too)
Energy Recovery only. We can offer a wheel only, heat pipe, or fixed core units. The energy recovery can be standalone or part of a system. The Lifebreath Metro series has a small footprint and can be matched to individual units to allow individual control.
A Noteworthy Product: United Cool Air’s Alpha Air. A complete indoor solution for up to 500 cfm of outside air. Incorporating the concept of 4 air connections (outdoor, exhaust, return and supply air), they incorporate a small heat pump compressor and 2 heat exchanges to allow this unit to deliver dry neutral air 365 days a year. Perfect a match for VRF systems, schools and more Learn More