502
Thermo AC/DC
5 Troubleshooting
Heater can not be switched off.
•
Supply voltage (24V) not switched off
•
HV small distribution board defective
•
Diodes in LV wiring harness defective (if applicable,
heater may be hooked-up incorrectly).
Heater does not heat.
•
No HV supply connected / active
•
HV fuses defective or not active
•
Ground fault interrupter or insulation monitoring
device (IMD) defective or not active
•
HV small distribution board defective
•
Heating cartridge(s) defective
No HVIL (Interloop) signal (if existent)
•
SC600 respective the control unit does not transmit
a HVIL signal
•
HVIL contact is not established
•
Hood not (correctly) mounted
•
HV cable not connected
•
HV control wiring harness (24V) not connected or
cable defective
Heating power too low
•
HV supply power too low
•
Heating cartridge(s) defective
Heating power too high
•
HV supply power too high
•
Overheating, temperature limiter has triggered
•
Control thermostat defective
Heater stops as the connected heat exchangers provide
insufficient heat.
Flow rate too small, because
•
Air in the heater, heat exchanger or in system
sections.
•
Taps/valves (flow controllers) throttled,
contaminated, closed.
•
Contaminations in the system, e.g. filters or at
bottlenecks.
•
Circulating pump delivery rate insufficient
(air in pump housing).
•
Insufficient frost protection.
•
System resistance too high (especially high in the
cold).
•
Circulating pump defective.
Heat exchanger provides not enough heat, because
•
Air in the heat exchangers and/or system sections.
•
Antifreeze content too high.
Approximate flow rate determination:
Heat flow [kW] according to type plate
Flow rate in [l/h] =
x 860
Temperature difference
∆
t in [K] or [°C]
measured on the heater between water inlet and water outlet
(e.g. using contact thermometer)
Table 501: General error symptoms
Error symptom
Possible cause
Summary of Contents for Thermo AC 070
Page 47: ...memos...
