9
ENG-021B/f.
Fig.11 Electric installation
E1 - heating box [1]
BV - differential pressure switch
[2]
Q4 - power limiter
F1 - WT3 safety temperature lim-
iter [3]
XG - heating box terminal
Fig.12 Example electric con-
nections with a priority
switch
K1 - priority switch
K2 - contactor
F1, F2 - fuses of the appliances
Repairing the above is not covered by the guarantee. If the heater breaks down (and it is caused by none of the
above reasons) you need to contact an authorised service to have it repaired.
- there might be a failure on power supplies,
- the rate of flow through the heater is not sufficient (filter blocked with
impurities or incorrect setting of the flow regulating valve).
- if the heating is weak or it does
not heat up at all:
- see if the plug [6] is connected properly to the socket,
- there might be a failure of power supplies off
- the indicators on the case are
Cut off power supplies before
taking the case off.
If you notice any of the following signs of faulty work, check if:
Example preferential switches: ABB STOTZ:
for 9..15kW
- E452-5.7 6,7 ÷ 30A;
for 18..24kW
- E451-15 18 ÷ 55A.
Alternatively, you may use a specially reconstructed differential pressure switch. To find out more, please
contact any of our authorised services.
11
12
Faults
