Rotex HPSU compact 308 - Page 45

8 x Faults and malfunctions
BA ROTEX HPSU compact 4 - 09/2013
45
Hot water does not warm
up
DIP switch configured
incorrectly
● Have the system checked
by a ROTEX heating
technician.
Hot water supply switched off (e.g. time pro-
gram is in the economy phase, parameters for
hot water supply have been set incorrectly).
● Check the operating mode setting.
● Check th
e request parameters.
Storage tank charging temperature too low. ● In
crease the target hot water temperature.
Draw-off rate too high. ● Reduce the draw-off rate, limit throughput.
Output of heat pump too low.
● Check the switching times for room heating and hot
water supply for overlaps.
Water volume in system too low
● Check
the water volume and the associated primary
pressure in the expansion tank, if necessary top up
the water and reset the primary pressure.
Optional: Backup heater (BUH) not switched on.
● Have the system checked
by a ROTEX heating
technician.
Room cooling does
not cool
Water flow too low.
● Check th
at all stop valves of the water circuit are
completely open.
● Check that the expansion tank is defective.
● Bleed system com
pletely.
● Using the controller (rotary switch position ) check
whether sufficient water pressure (> 0.5 bar) is
available.
● Have the system checked
by a ROTEX heating
technician.
Cooling" turned off (e.g. switching time 
programme is in the setback phase, exterior
te
mperature too low).
● Check th
e operating mode setting.
● Check th
e request parameters.
● Check the setting of time a weekday in the control
system.
Refrigerant compressor is not working.
● Wait until minimum water temperature is reached
(15 °C). At a low water temperatur
e the system may
use the optional backup heater (BUH) first to reach
the minimum water temperature.
● Have the system checked
by a ROTEX heating
technician.
System is in the operating mode "heating". ● Switch the operating mode to "Cooling".
Cooling effect of
room cooling too little
Water flow too low.
● Check th
at all stop valves of the water circuit are
completely open.
● Check
that the water filter is dirty.
● Check that the expansion tank is defective.
● Bleed system com
pletely.
● Using the controller (rotary switch position ) check
whether sufficient water pressure (> 0.5 bar) is
available.
● Have the system checked
by a ROTEX heating
technician.
Water volume in system too low.
● Have the system checked by a ROTEX heating
technician.
Quantity of refrigerant in the
system too low or
too high.
● Have the coolant level checked by a ROTEX
specialist heating technician. Have him check the
system for leaks.
Malfunction Possible cause Possible solution