Operational Problems - Danfoss DHP-H Installation And Service Instructions Manual

1. First measure the sensor including the cable.
2. Then measure the sensor only.
15 .3 Operational problems
Heat pump in almost continuous operation
Cause
Incorrectly dimensioned
Lack of refrigerant
Increased power output
Higher hot water con-
sumption
Incorrect flow in cold/hot
circuit.
Air in the system
The heat pump has short operating intervals despite heat demand
Cause
Room set point too high.
Curve too high, poor
heating system circula-
tion.
Closed radiator valves.
Insufficient water volume
in the heating system.
Element too small.
Tight fitting system, poor
pipe dimensions.
Heat pump runs on auxiliary heater
Cause
Output demand is too
great for the compressor
output.
The heat pump produces
peak heat.
The compressor cuts in
for high return.
The compressor cannot
run due to alarm.
The heat pump has too high energy consumption
Cause
Short active collector
Dry bore hole
Incorrectly set control
computer
Incorrect sensor heating
contact
Changed conditions
Compressor incorrect
phase sequence
High curve
4
Troubleshooting
1. Check cooling
2. Changed conditions
( increased power output, increased hot water con-
sumption)
3. Check refrigerant amount
Troubleshooting
• P oor flow, starts on hysteresis value (low water
volume)
• Poor pipe system
• Small radiators
• Heat pump too large
Troubleshooting
1. Is the control computer correctly set (auto curve)
2. Integral value reached AH start
3. Max return temperature (high)
4. Alarm? Indicator RP = 0
5. HP produces peak heat
6. Dimensioning / Changed conditions
7. Incorrect phase sequence compressor
Troubleshooting
1. Is the control computer correctly set (auto curve)
2. Integral value reached AH start
3. Max return temperature (high)
4. Alarm? Indicator RP = 0
5. HP produces peak heat
6. Dimensioning / Changed conditions
Incorrect phase sequence compressor
1. Short active collector
2. Incorrect ∆t on hot/cold side
3. Over heating/cooling
-
-
Room set point / curve setting
too high
Check sensor (outdoor, supply
pipe, room)
Wiring to sensor
Check 3-way valve (insert,
motor)
-
VMBMA102
Remedy
Remedy
Remedy
Remedy