aldes H/E280 - Page 8

Residential HRV/ERV
8
Add a ‘‘T’’
recommended
for H110-TF
Partially Ducted System – Conguration
Partially Integrated Duct Conguration
In a partially ducted conguration, individual exhaust grilles in bathrooms, laundry rooms,
and kitchens draw stale air. Each location with a stale air duct could also have a timer that
will initiate high-speed ventilation. Fresh air is distributed by the Air-Handling Unit (AHU) of
a forced-air heating or air conditioning system. The connection to the forced-air system is
typically to the return ducting or plenum of the AHU. See section “Interlocking the HRV/ERV
to an Air-Handler/Furnace Blower” on page 18.
While this conguration is common in commercial installations, it is not always recommended
for residences due to the following:
1. In this case, the AHU must run continuously or be interlocked to operate with the HRV/
ERV to avoid loss of balanced supply and exhaust airows.
2. In multi-speed AHU’s, balancing must be conducted on the most frequently used speed,
but the HRV/ERV may not remain in balance at other speeds. The same is true if the AHU
has multi-speed blowers.
3. In warm, humid seasons, continuous operation of the AHU causes evaporation from the
cooling coil, resulting in a loss of humidity control. Failure to operate the AHU with the
HRV/ERV may also result in condensation in the supply plenum and ducting.
4. Continuous operation of the AHU may cause drafts in the winter.
INDOOR AIR
SUPPLY AIR
OUTDOOR AIR
EXHAUST AIR
6 ft min
HVAC AHU
HVAC RETURN DUCT
HVAC SUPPLY DUCT
*Note: Port congurations
are generic and do not
represent specic models
Supply Air Ducted to
HVAC Return Duct
Dedicated Exhaust
Grilles