33
Characteristics of the mechanical ventilation sys-
tem
Action
Integral electric preheater coil is faulty or thermal breaker has responded.
System
with
external electric preheater coil:
■
At low outside temperatures the external electric pre-
heater coil often switches on.
■
At outside temperatures below
–
10 °C the supply air
flow is often reduced.
■
The ventilation unit frequently switches off at outside
temperatures below
–
10 °C.
Check the connections of the integral electric pre-
heater coil (see page 37). Replace preheater
coil if required.
System
without
external electric preheater coil:
■
At low outside temperatures the supply air flow is of-
ten reduced.
■
At low outside temperatures the ventilation unit fre-
quently switches off.
Troubleshooting
Faults without fault display
5793 605 GB
Diagnosis
