Problem – Alarm electric heater error
Cause
Troubleshooting
Remedy
1. The overheating protec-
tion has tripped.
Check if the overheating protection has tripped.
If the overheating protection has tripped,
reset it.
2. Phase drop.
The alarm occurs when 230
V is not registered between
L2 on the circuit board and
N. Does not apply if MAX
STEP = P.
▪
Check if the overheating protection has tripped.
▪
Check if any cables at the circuit board or overheating
protection are loose or damaged.
If the overheating protection has tripped,
reset it.
If the cables are loose or damaged, secure
or replace them.
3. Overheating protection
fault, cannot be reset.
Press the reset button, measurement check for 230 V on
the incoming and outgoing connections.
If the overheating protection is defective,
replace it.
4. Flow sensor fault.
Check what the flow sensor shows. Is it a plausible/actual
value?
Measure the resistance of the sensor, check against the
ohm table in Measurement points .
If the sensor is defective, replace it.
5. No or insufficient circula-
tion in the heating system.
Check:
▪
That the circulation pump spins
▪
That the shut-off valves are open.
▪
That the strainer is not blocked.
▪
That there is no air in the heating system.
The circulation pump may have jammed. If
so, open the bleed screw and try to release
the paddle wheel using a screwdriver for
example.
Open closed valves or taps.
Check, and, if necessary, clean the strainer.
If necessary, bleed the heating system ac-
cording to the installation instructions
Problem – Alarm circulation pump
Cause
Troubleshooting
Remedy
The circulation pump’s inte-
grated alarm has deployed.
(Only applies to not valid )
▪
Air in the heating system.
▪
Has the circulation pump jammed?
Vent the heating system and TWS coil.
If the circulation pump has jammed, there
is an integrated shake function that at-
tempts to shake itself loose up to a maxi-
mum of 5 times, if it does not succeed, an
alarm will occur.
Try cutting the voltage to the heat pump to
stop the alarm and then manually run the
circulation pump.If the alarm recurs, repeat
the procedure several times. If this does not
help, replace the circulation pump.
Service Instructions
DHP-AQ
Danfoss Heating Solutions
VMGFJ202
19
