63
IS
THERE STILL
A PROBLEM?
NORMAL
OPERATION
NO
NO
YES
YES
FAULTS
POSSIBILE CAUSES
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
B
Drawing D.H.W:
When you turn on a tap
burner switches off
Drawing D.H.W:
radiators heat up in summer mode
Drawing D.H.W:
insufficient hot water
temperature
Drawing D.H.W:
noisy operation
Decrease/increase
heating circuit pressure
Repeated shutdowns
Repeated intervention of safety thermostat
When cold water tap turned off, the boiler
ignites
Insufficient radiator temperature
- check temperature probes
- faulty D.H.W. flow switch
- faulty 3-way valve
- check temperature probes
- check gas pressures
- check water flow rate
- primary heat exchanger faulty or
lime-scale deposits
- low heating system water pressure
- check gas pressures
- check temperature probes
- check for leaks on the heating circuit
- faulty filling-loop
- expansion vessel faulty
- faulty detection electrodes
- check gas settings
- check flame detection electric circuit
- check temperature probes
- overheat thermostat not calibrated correctly
- air in primary water circuit
- drop in pressure in the water mains, with
consequent water hammer
- check C.H. temperature probe
- check by-pass and pump speed
- check gas pressures
FC P014