Operating instructions

70
2. Check throughput of affected heating
circuits. Recommended temperature
differential between heating flow and
return approx. 8 K.
3. Hydraulically balance the connected
heating circuits.
4. Check the outside temperature sen-
sor (see page 73).
5. Increase the set room temperature
for standard mode and match the
heating curves.
Operating instructions
6. Enable heating operation via the inte-
gral instantaneous heating water
heater (if installed) (see page 96).
No display indication on the programming unit
1. Switch ON system ON/OFF switch.
2. Check heat pump control unit fuse;
replace if required (see page 74).
3. Check whether there is power at the
control unit; switch ON power supply
if required.
4. Check the plug-in and threaded con-
nections.
5. Replace programming unit if
required.
6. Replace PCB 2 (main PCB) if
required.
Troubleshooting
Steps if the room temperature is too low
(cont.)
5441 603 GB