Danfoss DHP-AX, Инструкция по установке и обслуживанию

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Service – 61 VMBMH302
Problem – Runs on electric heating element
Cause Troubleshooting Remedy
1. Operating mode AUX. HEATER
is selected. If this operating mode is selected, the aux-
iliary heater is used for heating and hot
water production, not the compressor. If AUX. HEATER mode is selected and you
no longer want it, change to AUTO, the
heat pump then controls both the com-
pressor and auxiliary heater.
2. The compressor cannot run due
to an alarm. Check the alarm that is indicated in the
display. Rectify the problem and rest the alarm.
See section
15.5 Operational problems .
3. The integral value has reached
the start level for the auxiliary
heater. Check what the integral value is in the
control system. If the auxiliary heater is in operation
because the integral value has counted
down to the start value, the computer
reacts as it should, see section
11 Heat
pump for further information.
4. Peak heat operation (anti-legio-
nella function) is running. Check if the heat pump runs peak heat.
See the instructions for the relevant
model. Peak heat operation occurs in connection
with hot water production with the set
interval. The compressor should then start
to produce hot water and 2 minutes later
the auxiliary heater starts, the compressor
should then stop and the stop temperatu-
re is reached with only the auxiliary heater
connected. Take no corrective action.
5. The heat pump has stopped on
HIGH RETURN. • Check what the MAX RETURN value is set
at in the heat pump’s control computer. It
must be adjusted to the unit’s maximum
supply temperature and the system’s delta
temperature so that it does not cut at too
high a return temperature when the hig-
hest supply temperature is transmitted.
• Check what the return line sensor shows,
is it a plausible/actual value? If not, take a
resistance reading from the sensors and
check against the ohm table in section
15.3 Measurement points .
If the MAX RETURN value is not adjusted
for the system according to the trou-
bleshooting window, adjust it.
If the sensor is defective, replace it.
6. The compressor runs back-
wards. The incoming phases have
the incorrect sequence (only app-
lies to 3-phase heat pumps).
If the compressor runs backwards,
it will not cope with compressing
the refrigerant and therefore does
not produce the correct power,
which leads to the control system
requesting auxiliary heating.
• If the text ERR PHASE SEQ. appears in the
display when the heat pump is powered,
(only appears in the first 10 minutes) this
means that the phases have the incorrect
sequence.
• When the compressor is running, check
the pressure pipe temperature by feeling
the pressure pipe. If the phases are cor-
rectly sequenced it should be hot (not just
warm) even a distance from the compres-
sor .
• When the compressor runs with the pha-
ses incorrectly sequenced a strange noise
may be heard (loud, rattling) when the
compressor runs backwards.
If the phases are in the incorrect order,
switch two incoming phases at the main
terminal block and recheck according to
the troubleshooting window.
7. Changed conditions Have you
increased your heating and/or
hot water demand? • If the heat pump has been dimensioned
for a certain demand and this demand is
increased, the heat pump might not be
able to maintain the desired room tempe-
rature.
• If hot water consumption increases, a lar-
ger proportion of time is used to produce
hot water, which means less time for heat
production (only applies to VL-systems).
If the heat pump cannot cope with the
demand, replace it with one with a higher
output or supplement it with a higher
output auxiliary heater.