MHG Heating ThermSelect, Assembly, Commissioning And Maintenance Instructions

Page: 75 / 100

ThermSelect®
9. Troubleshooting
75/100
Fault Cause Remedy
Fault with con-
denser motor con-
denser overload
(overheating of the
motor winding)
Failure of a phase Check supply line of 3-phase current
Mechanical failure due to lack of lubrication Request factory service
Winding protection defective Replace winding protection
Low refrigerant level Request factory service
Defect in the refrigerant regulation Request factory service
Operation with incorrect refrigerant Request factory service
Pressure gas temperature too high Request factory service
Fault current (FI)
circuit breaker ac-
tivates
Wrong allocation of neutral lead for spe-
cial/normal tariff Check device wiring
heating pump
locked
Special tariff supply line interrupted (off-time
preset by utility company);
bivalence point undercut Check blocking times for the special tariff
connection;
check parameters (RVS 61, Line 2910)
Evaporator ices up
quickly
High humidity and temperatures of 3-8°C
lead to quick icing up of the evaporator. Decrease time until forced thaw (parameter
line 2963)