Viessmann OC208HM, Инструкции по обслуживанию для подрядчиков

Страница: 19 / 48

3. Recheck the superheating.
4. If required, repeat steps 1 to 3.
Note
Should the thermostatic expansion
valve fail to respond to the superheat-
ing adjustment, it may be stuck or
faulty and may need to be replaced.
Checking the evaporator parameters
Check the return temperature (ST1,
see page 32), flow temperature (ST2,
see page 32) and the water circulation
volume of the evaporator (if possible). Record the determined values in the
service report from page 39.
Checking the high pressure switch
Record the implementation of the
work in the service report from
page 39.
Checking the low pressure switch
Record the implementation of the
work in the service report from
page 39.
Checking the water side of the evaporator for contamination
The temperature differential between
the flow and the return temperature at
the plate-type heat exchanger must
be 5 to 8 K. The plate-type heat
exchanger may be contaminated at
temperature differentials > 8 K.
In this event, separate the heat
exchanger hydraulically and clean it
chemically or replace the exchanger. Note
Other causes for temperature differ-
entials
> 8 K could be a pump speed
that is too low or the contamination of
the water filter. Check these options
prior to working on the plate-type
heat exchanger.
Record the implementation of the
work in the service report from
page 39.
Further details regarding the individual steps
(cont.)
19
Commissioning, inspection, maintenance
5692
695
GB