Danfoss DHP-AX, Инструкция по установке и обслуживанию

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48 – Service VMBMH302
Cause Troubleshooting Remedy
15. Blocked evaporator on the
refrigerant side. Using manometer apparatus and ther-
mometer, check that the unit’s overhea-
ting is correct for the specific refrigerant. If the evaporator is thought to be block-
ed by oil for example, try blowing nitro-
gen through it to release the oil. If this
does not work, it must be replaced
Problem – Alarm HP (high pressure pressure switch)
Cause Troubleshooting Remedy
1. Blocked strainer in the heating
system. Check that the strainer is not blocked. Clean the strainer if necessary.
2. Air in the heating system. Listen for air in the heat pump and hea-
ting system. Bleed the heating system according to
the installation instructions.
3. Closed or partially closed ther-
mostats/valves in the heating
system. Check that the thermostats/valves in the
heating system are open. Open closed thermostats/valves.
4. The circulation pump that is
defective or has jammed. Is there voltage to the circulation pump? In the control system’s manual test menu
check that the circulation pump is active.
Check if there is voltage to the circulation
pump, if there is, and it does not run, the
circulation pump is jammed. If this is the
case, open the bleed screw and try to
release the paddle wheel using a screw-
driver for example (Does not apply to
heat pumps in the Optimum series).
If there is no voltage to the circulation
pump, check if there is voltage from the
I/O card, see wiring diagram. If there is
voltage from the I/O card, check the com-
ponents between the I/O card and the
circulation pump.
If a component is defective, replace it.
5. Shut-off main tap in heating
system. Check that the main tap is open. Open closed main tap.
6. Cable break or loose cable to
high pressure pressure switch. • Check that both cables are connected
on the pressure switch.
• Using the buzzer, check that there are
no cable breaks. In order to do this, dis-
connect the cables from the pressure
switch and circuit board.
If a cable has come loose, connect it.
If there is a cable break, replace the cable.
7. The operating pressure switch
does not open. • Incorrect pressure switch installed.
Same or higher break pressure than high
pressure pressure switch. See marking.
• Pressure switch fault, opens at a higher
pressure than indicated (mark pressure).
Check using the manometer apparatus.
• Defective pressure switch, never opens.
If the operating pressure switch does not
open, replace it.
8. The high pressure pressure
switch opens too soon. • Incorrect pressure switch installed. As
low or lower break pressure than opera-
ting pressure switch. See marking.
• Pressure switch fault, opens at a lower
pressure than indicated (mark pressure).
Check using the manometer apparatus.
• Defective pressure switch, always open.
If the high pressure pressure switch
opens too soon or is always open, replace
it.