15 Troubleshooting
15.1 Alarm list
Shown in display in the event of an alarm. To reset alarms 1-5, set the operating mode to OFF or cut the power supply.
Message Meaning
HIGHPRESS ERROR Tripped high pressure switch. Compressor stopped. No hot water production.
LOWPRESS ERROR Tripped low pressure switch. Compressor stopped. No hot water production.
MOTOR P ERROR Deployed motor protection (Over current relay compressor). Compressor stopped. No hot
water production.
BRINE OUT Brine out is less than the set minimum temperature. Compressor stopped. No hot water
production.
BRINEFLOW LOW Flow sensor not active during last start. Compressor stopped. No hot water production.
ADD. HEAT Overheating protection deployed. No additional heat.
SENSOR OUTDOOR Fault in outside sensor. Zero degrees used for calculations.
SENSOR FRONT Supply line sensor error. Everything stops except the heating system’s circulation pump.
SENSOR RETURN Return sensor fault. Return temperature = Supply line – 5 is used. Calculated supply tem-
perature limited to maximum 45°C.
SENSOR HOT WATER Fault on sensor for start temperature. No hot water production.
SENSOR DEFROST Defrost sensor fault. Heat and hot water production is controlled from the outdoor sensor’s
value instead. (Applies to DHP-A, -AL)
MS FAN Deployed motor protection for outdoor unit fan. Compressor stopped. No hot water pro-
duction. (Applies to DHP-A, -AL)
SENSOR COOLING Sensor fault. Cooling function stops.
15.2 Measurement points
Conversion table for sensors
NOTE! When reading the resistance of the sensors, the sensor leads must first be disconnected from the control equipment.
Outdoor sensor Other sensors
°C
ohm, Ω
°C
kilo ohm, kΩ
-30 1884 0 66.3
-25 1443 5 52.4
-20 1115 10 41.8
-15 868 15 33.5
-10 681 20 27.1
-5 538 25 22.0
0 428 30 18.0
5 343 35 14.8
10 276 40 12.2
15 224 45 10.1
20 183 50 8.5
25 150 55 7.1
30 124 60 6.0
35 103 65 5.0
40 86 70 4.2
75 3.7
80 3.1
85 2.7
90 2.3
95 2.0
1. Disconnect the sensor cable at the I/O card.
2. First measure the sensor including the cable.
3. Then measure the sensor only.