Troubleshooting - Danfoss S 22 Instructions For Installation And Use Manual

Instructions for installation and use

12. Troubleshooting

Fundamental
In the event of disruptions to operation , you should fundamen-
tally - before commencing the actual troubleshooting - check
whether:
• the system is correctly connected
• the district heating supply temperature is at its normal level
• the differential pressure is at its normal level - ask your district
heating supplier if necessary
Problem
No heat
Uneven distribution of heat
Poor cooling
No heat
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DKDHR
S 22
• there is a power supply to the system - pump and automatics
• the dirt strainer in the district heating supply pipe is clean
• there is air in the system (if the system is vented)
Possible cause
Dirt strainer in the district heating or
heating return line clogged.
Filter in district heating meter clogged.
Defective or incorrectly set differential
pressure controller.
Air pockets in the system.
Air pockets in the system.
Insufficient heating surface / radiators
too small compared to the total heating
requirement of the building.
Poor utilisation of the existing heating
surface.
Defective actuator - or possibly dirt in
the valve housing.
Automatic components/controller
incorrectly adjusted or defective - or
possibly power outage.
The pump is not working.
The pump is set at too low speed of rota-
tion (not all system types).
Air pockets in the system.
VI.IE.D1.02
Solution
Clean the filter / dirt strainer.
Clean the filter (in consultation with the
district heating plant).
Check the functions of the differential
pressure controller - if necessary, clean the
valve seat.
Vent the system thoroughly - see the in-
structions
Vent the installation thoroughly - see the
instructions.
Increase total heating surface.
Turn on all radiators and prevent the radi-
ators in the system from becoming warm
at the bottom.
Check that the actor is functioning cor-
rectly - clean the valve seat if necessary.
Check that the controller setting is cor-
rect - see the separate instructions for the
controller.
Check the power supply.
Temporarily set the actuator to "manual"
control - see the instructions for the heat-
ing system.
Check that there is a power supply for the
pump, and that it is operating.
Check that there is no air in the pump
housing - see pump manual.
Set the pump to a higher speed - see the
instructions for the heating system.
Vent the installation thoroughly - see the
instructions.
Danfoss District Energy