Mark Fohn Livret Technique page 8

3.4 Check the pre-pressure
The gas pre-pressure at the gas control unit must be measured when the appliance is in operation.
The pre-pressure is indicated on the appliance's type plate.
3.5 Check the safety thermostat [6]
Check the correct operation of the safety thermostat before proceeding to commission the appli-
ance. Correct operation of the safety thermostat guarantees the operational reliability and durabil-
ity of the appliance. When the Föhn is delivered as a complete unit, this is installed and set at the
factory.
Setting the safety thermostat:
The safety thermostat (STB) is unalterably set to 100°C; when this temperature is reached, the
burner is switched off and the thermostat mechanically locked.The thermostat can only be reset
manually;
– maximum control thermostat (STW) in the locked state (90°C). The burner is temporarily
switched off when this temperature is reached;
– fan thermostat Tmin:
3.6 Motor overload safety.
In accordance with generally applicable regulations, all electric motors must be protected against
overheating and overloading by a thermal overload safety. This trips the relay. The thermal over-
load safety must be reset manually.
Thermal overload safety
The thermal overload safeties are set and sealed at the factory. Check the current draw of the fan
motor; if the current draw is too high, the external static pressure in the air system is probably
lower than the information indicated on the type plate. If the external resistance in the air ducting
is found to be incorrect, the customer must correct this to correspond to the value indicated on
the type plate. Never operate motors that have been overloaded. This renders the guarantee
void.
3.7 Shutting down the heater
For short periods of time:
– Set the room thermostat to the minimum temperature.
– The burner switches off and the fan continues to operate until the fan thermostat switches off
the fan motor.
For longer periods of time:
– Set the room thermostat to the minimum temperature.
– After the automatic fan post-ventilation time has elapsed, the power supply to the appliance
can be disconnected.
8
40°C, fan is switched on.
30 , fan is switched off.