Instructions condensing Air heaters type XR version XR-GB-4001-a
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5
Functioning of the unit
5.1 General
The unit can heat as well as ventilate. By using the temperature-sensor on the unit and the one
in the room-thermostat, the temperature-difference between the two in the room is monitored.
Should the difference become higher than a set value, due to the fact that warm air has
accumulated underneath the roof, the system-fan will start and push the warm air down, acting
as a de-stratification fan.
5.2 Burner cycle
The status and burner cycle is showed on the display in the heater
Display Status
Description
0
Stand-by
Standby, waiting for heat demand
1
Reset
Software reset
3
Pre-check
Zero position check pressure switch
4
Pre-purge
30 seconds of pre ventilation from the combustion fan. The
pressure switch is checked.
5
Pre-ignition
Ignition without opening the gas valve
6
Igniting
Ignition (5 sec), gas valve opens
7
Flame check
Check if the flame is present
8
Burn
The heater burns and starts to modulate.
9
Minimum
Before the flame stops, the burner will modulate to minimum
power
10
Burner off
Gas valve closes, the flame stops
11
Post Purge
Burner fan purges with fresh air
System fan cools the heat exchanger
Minimum burn time 4 minutes!
The heater will always burn minimum 4 minutes, even if the heat demand stops. This to avoid
an unnecessary large amount of start and stops.
The heater will try 2 times to ignite before it stops and gives an error.
5.3 Delta-T-regulation (temperature controlled de-stratification fan)
In case there is no heat demand, the delta-T-regulation will be active.
When the temperature-difference between the sensor on the unit (the NTC) and the sensor in
the thermostat is bigger than the set value (factory setting standard 8°C), the system fan will
start, at a regulated speed, depending on the differential temperature difference. This operation
ensures an even temperature distribution throughout the building, thus acting as a fully
automatic variable de-stratification fan.
Switch of delta-T-regulation
Should this delta-T-regulation not be required, in the Menu Program Settings on the room
thermostat this regulation can be switched off. See user manual of the special Winterwarm
Room thermostat.
5.4 Summer ventilation
It is possible to let the ventilator run on a certain speed in the summer. Please follow the
instructions in the manual from the thermostat.
