Installation guide

50
VMBME102
Problem – Shrieking whistling noise
Cause Troubleshooting Remedy
1. Whistling expansion valve. 1. Take overheating readings, adjust to the
recommended value.
2. Open and close the valve fully in and out.
3. Adjust the expansion valve to recom-
mended overheating value again.
Check if the noise has stopped, if not, con-
tinue with point 2.
Continue with point 3.
If the problem persists, replace the expan-
sion valve.
2. Noise from the soft-starter. Measurement check the input and output
phases for the soft-starter as well as the
control signals from the control computer,
see wiring diagram.
If the soft-starter is defective, replace it.
3. The compressor’s IPR valve opens. The compressor has an integrated IPR valve
that opens at 28 ±3 bar.
When the valve opens, pressure equalizes
between the compressor’s high and low
pressure side and a milling/whistling sound
is heard.
To establish whether the valve opens at the
correct pressure, connect a manometer on
the high and low pressure side.
When the valve opens, this is indicated by
the pressure on the low pressure side rising
and reaching the pressure on the high pres-
sure side.
Check at what pressure the valve starts to
open.
If it opens at a too low pressure, replace the
compressor.
Problem – Noise – miscellaneous
Cause Troubleshooting Remedy
1. Vibrating protective sleeves on the pres-
sure switches.
Establish where the vibration noise is com-
ing from.
Prevent the protection sleeve vibrating by
using insulation tape for example.
2. Vibration noise from the electrical instal-
lation.
Check for electrical steps or similar devices
screwed to the heat pump and wall. These
can cause vibrations and noise.
Carry out according to the installation
instructions.
3. The heat pump is not level. Check that the heat pump is level by using
a spirit level.
Check that the heat pump is supported by
all four feet
If the heat pump is not level, adjust using
the feet.
14.6 Operational problem – Hot water
Problem – Temperature and/or quantity
Cause Troubleshooting Remedy
1. Defective 3-way valve motor. Check the function of the 3-way valve, that
it runs between the end positions by run-
ning a manual test.
If the motor is defective, replace it.
2. Jammed 3-way valve insert.
The valve is not secure and releases hot
water to the radiators during hot water
production.
Detach the motor and test closing and
opening of the valve by pressing the con-
trol arm
If the insert jams, remove and clean it, or
replace it.
3. Air in TWS coil or water outer jacket. During hot water production:
• Listen for air.
• Check the temperature difference
between supply and return pipe.
Bleed the system.
A Large temperature difference can indicate
air in the system.