Installation Guide
Termix HD MIX Compact 28
7.0 Troubleshooting
7.1 Troubleshooting in general
In the event of operating disturbances, the following basic features
should be checked before carrying out actual troubleshooting:
•
the substation is connected to electricity,
•
the strainer on the DH supply pipe is clean,
•
the supply temperature of the DH is at the normal level
(summer, at least 60 °C - winter, at least 70 °C),
•
the differential pressure is equal to or higher than the normal
(local) differential pressure in the DH network – if in doubt, ask
the DH plant supervisor,
•
pressure on the system - check the HE pressure gauge.
Authorized personnel only
Assembly, start-up and maintenance work must be performed by
qualified and authorized personnel only.
7.2 Troubleshooting HE
Problem
Possible cause
Solution
Too little or no heat.
Strainer clogged in DH or HE circuit
(radiator circuit).
Clean gate/strainer(s).
The filter in the energy meter on DH circuit
clogged.
Clean the filter (after consulting the DH
plant operator).
Defective or wrongly adjusted differential
pressure controller.
Check the operation of the differential
pressure controller – clean the valve seat if
required.
Sensor defective – or possibly dirt in the
valve housing.
Check the operation of the thermostat –
clean the valve seat if required.
Automatic controls, if any, wrongly set or
defective - possibly power failure.
Check if the setting of the controller
is correct – see separate instructions.
Check the power supply. Temporary
setting of motor to “manual” control – see
instructions on automatic controls.
Pump out of operation.
Check if the pump is receiving power and
that it turns. Check if there is air trapped in
the pump housing – see pump manual.
The pump is set at too low speed of
rotation.
Set the pump at higher speed of rotation.
Pressure drop – the pressure drop on
the radiator circuit shows lower than
recommended operating pressure.
Fill water on the system and check the
functioning of the pressure expansion
vessel if required.
Air pockets in the system.
Vent the installation thoroughly.
Limiting of the return temperature
adjusted too low.
Adjust according to instructions.
Defective radiator valves.
Check – replace.
Uneven heat distribution in building
because of incorrectly set balancing valves,
or because there are no balancing valves.
Adjust/install balancing valves.
Diameter of pipe to substation too small or
branch pipe too long.
Check pipe dimensions.
Uneven heat distribution.
Air pockets in the system.
Vent the installation thoroughly.
Danfoss District Energy
VI.GP.E1.02 / LUK42860
DEN-GT
15
