Regular Checks; Checking Operation; Check The Water Level In The Heating Circuit - Danfoss DHP-AT User Manual

User Guide
8

Regular checks

8.1

Checking operation

During normal operation, the alarm indicator is hidden to show that everything is OK. When an alarm is triggered, the alarm indicator
flashes and at the same time an error code is shown in the display.
Error code Description
00 Communication failure
01 Return water sensor (T9) failure
02 Supply water sensor (T8) failure
03 Water flow switch protection
04 Phase sequence error (only applies to 3-phase models)
05 Excessive temperature difference protection of supply and return water
06 Internal electrical heater overheat protection
07 Condenser overheat protection
08 Hot water tank sensor (T3) failure
09 Buffer tank sensor (T2) failure
10 High pressure protection
11 Low pressure protection
12 Supply water temperature too high
13 Supply water temperature too low
14 Return gas temperature sensor (T5) failure
15 Exhaust gas temperature sensor (T4) failure
16 Exhaust gas temperature overheat protection
17 Null
18 Frost protection, step 2 (non-fault)
19 Frost protection, step 1 (non-fault)
20 Air temperature sensor (T1) failure
21 Heating coil sensor (T7) failure
22 Cooling coil sensor (T6) failure
23 Exceeded operation range warning (non-fault)
8.2

Check the water level in the heating circuit

The line pressure of the installation must be checked once a month.
The external manometer (if available) must show a value between 1-1.5 bar. If the value is below 0.8 bar, when the water in the heating
system is cold, the water must be topped up (applies in the event of an empty expansion tank).
Ordinary tap water can be used when topping up the heating system. In certain exceptional cases, the water quality may be poor (for
example very hard water) and is not suitable for filling the heating system. If unsure, contact your installer.
The closed expansion tank contains an air filled bladder that absorbs variations in the heating system's vol-
N
ume. Under no circumstances may it be drained of air.
Danfoss Heating Solutions
DHP-AT
Check the alarm indicator regularly to ensure that the appliance is work-
ing correctly. In the event of an alarm the heat pump will, if possible, sup-
ply heating to the house, primarily with the compressor, secondarily with
the internal electrical heater.
The hot water production will stop to indicate that something notewor-
thy has occurred.
VUGFC20202
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