Danfoss DHP-A Service Instructions Manual page 49

10.4.3 Noise
Table 25. Problem – Noise problem in the radiator system
Cause
1. Flexible hoses missing.
2. Incorrectly installed flexible hoses.
3. Installing/suspending pipes.
4. Clicking.
5. Circulation noise (whistling noise in
the heating system).
Table 26. Problem – Loud compressor noise
Cause
1. Phase drop.
The compressor attempts to start or
operates on two phases (only applies
to 3 phase heat pumps) .
2. Touching pipes – vibrations.
3. Compressor fault.
Troubleshooting
Flexible hoses must be installed according
to the instructions.
Flexible hoses must be installed according
to the instructions.
Check if the mountings are too rigid, right
type, right sizes and/or installed too close
together.
•
Establish when clicking occurs, during
heating and/or in connection with
completed hot water production?
•
Locate the clicking noises.
Check the heating system.
•
Closed valves, choke valves, adjuster
valves or other restrictions in the radia-
tor system can cause circulation noise.
•
Is the heating system correctly adjus-
ted for flow?
•
Too great a flow in the heating system
can cause circulation noise.
Troubleshooting
1. Check that there is 400 V between
incoming phases on the heat
pump.
2. If there is supply to the heat
pump, measure the voltage for all
electrical components all the way
to the compressor, see wiring dia-
gram.
Establish which pipe(s) is/are causing the
problem.
Determine whether the compressor is
unusually loud.
Remedy
Install flexible hoses according to the
instructions.
Install flexible hoses according to the
instructions.
If something seems to be incorrect
according to the troubleshooting win-
dow, carry out corrective actions.
A surge tank can be installed on the sup-
ply line to mix the hot water with the
existing, slightly cooler, water, before it
goes out to the radiators.
Try lubricating lead-ins in walls, ceilings
and floors with silicone spray.
If the incorrect type of valve is used to
choke the flow, replace with the correct
type.
If the heating system is not correctly
adjusted, make adjustments.
Can the heating system be run at a
lower flow?
Remedy
Check where the phase drop is and rec-
tify.
Try to release any tensions that cause
the vibrations.
If the compressor is defective, replace it.
Service instructions VMGFC302 – 47