Traditionally, we have had a separate heating and ventilation system in the house. As the requirements are tightened you now have the option of using only the ventilation system to heat the house.
A “low-energy house” has lower energy/year compared to the requirements of the National Housing Board and it is built using well insulated and airtight envelopes.
In order for a low-energy house to work, a controlled HRV system is required. A HRV system not only makes ventilation and heat recovery possible, but due to the low energy requirements of the dwelling, the system can even operate to heat and cool the home. Hydronic floor heating and radiators are replaced by the airborne heating system and each apartment is its own fire compartment. Financially, this will often be both a cheaper and a less complicated alternative. To get an optimal system/indoor climate requires cutting-edge technology, including in the form of a custom control, to get the special features you need in a low-energy or passive house with air heating. For your REC Temovex unit you have the option “ECO2”, where we have the possibility to work with both forced heating and cooling flows, all with a variable control that allows for maintaining a uniform temperature.
“ECO2” means that if the normal flow of the fans is insufficient to maintain the set and desired temperature (set point) the fans will further increase their speed, up to the forced flow, to bring more heating or cooling. Forced ECO2 cooling works even if you do not have a cooling coil. The Temovex unit will then bring in cold air through the by-pass and as far as possible will cool through this.
If you compare different houses, you will see that there is a big difference in the load with an active family with children having a lot of cooking compared to a single person living alone. Using the REC ECO2 system, we will have an adapted heating and cooling (By-pass) flow even in apartment buildings.
A power requirement calculation per room (your project manager will help with this) is required to determine the heating coil and air flows. We look at air speeds and unit placement, to avoid draft. Depending on the heating requirement, supply air temperature may vary from +16 to +43 deg. The unit has a built-in heating coil, water or electric. With the REC Temovex Unit you also have the possibility to interlock the air flow with the cooker hood and compensate for the air flow when cooking.
Airborne heating with zoning
Zoning means that you are able to maintain a lower temperature in the bedroom compared to, e.g., the living room. In the example drawing below, you can see that the supply air duct is divided. On the part of the SA channel leading to the living room an extra duct heater (300 W) is mounted. Compared to a standard system for airborne heating the FTX unit is working with an SA temperature of about +35 degrees, the last 5-7 degrees taken by the duct heater. The following example makes use of the ‘master bedroom’ as a reference room in terms of temperatures for bedrooms. It is also where the room sensor is placed that the FTX unit is working with. The duct heater has a separate room sensor that is placed in the living room. Using zoning you will therefore always have a few degrees lower temperature in the bedroom than the living room.