Modes of Operation
The switch on the side of the unit is used to toggle between STANDBY, LOW speed and MEDIUM speed modes.
In order to activate HIGH speed, a jumper must be placed between the DEHUM + and DEHUM - contacts.
1. Continuous Ventilation Mode
In this mode of operation, both fans are operating and exchanging air
with the outside. The heat recovery ventilator (HRV) constantly
exchanges the air at the rate you select, either at low or medium
speed, and switches to high speed when activated by an optional
remote control. The "Low" and "Med" fan speed selection will cause the
unit to operate in continuous exchange mode at an exchange rate of
35% and 50% maximum airflow rating respectively. Continuous mode is
recommended, since pollutants are slowly but constantly being
generated in your house.
Air from
outside
Air to
outside
3.Defrost/Recirculation Mode (5 port "R" models)
The automatic defrost cycle for SHR R(D) / VHR R models of HRVs
consists of a damper defrost which allows air to recirculate throughout
the unit & home. When the supply air stream temperature goes below
-5°C (23°F), the exhaust fan shuts down, the supply fan goes to "High"
speed, and a damper closes the supply, opening a 5th collar. the
ambient air is then recirculated through the unit & home for a period of
5 minutes.
the unit will then resume normal operation for a time period of 25
minutes. this damper defrost cycle continues until the supply air
stream rises above 0°C (32°F).
Air from
House
2. Intermittent / Standby Mode (SHR(D) / VHR Series of HRVs)
the system is always on standby and operates at high speed when
activated by an optional remote control. "Standby" should be selected if
the user wishes to stop the unit from continuous exchange. We
recommend that the "Standby" mode only be used if your system is
equipped with an optional external control, in which case, the unit would
activate to "High" fan speed, until the control is satisfied and then return
to "Standby" (off).
Air from
House
Air to
House
4. Defrost/Fan shutdown (4 port models)
the automatic defrost cycle for SHR/VHR models of HRVs consists of a
fan shutdown. When the supply air stream temperature goes below
-5°C (23°F), the supply fan shuts down and the exhaust fan goes into
"High" speed. Ambient air is passed through the unit for a period of 5
minutes. the supply fan will then re-start and run at the presetspeed.
the exhaust fan will also slow down to the preset speed, and the unit
will operate in the run cycle for 25 minutes. this fan shutdown defrost
cycle continues until the supply air
stream rises above 0°C (32°F).
Air to
Air to
House
outside
* no exchange of air
Air from
fantech
5
House