16 | © Danfoss | Produced by Danfoss Redan A/S | 2020.08
145X2039
AN352656760258en-000101
13.
TROUBLESHOOTING GENERAL
In the event of operating disturbances, the following basic features
should be checked before carrying out actual troubleshooting:
• the station is connected to electricity,
• the strainer (if any) on the HS supply pipe is clean,
• the supply temperature of the HS is at the normal level,
• the differential pressure is equal to or higher than the normal
(local) differential pressure in the HS network – if in doubt, ask
the HS plant supervisor.
Authorized personnel only
Assembly, start-up and maintenance work must be per-
formed by qualified and authorized personnel only.
Problem
Possible cause
Solution
Too little or no DHW.
Strainer (if any) in supply or return line
clogged.
Clean strainer(s).
Defective or clogged non-return valve.
Replace – clean.
No electricity. Only if station are with DHW
circulation.
Check.
Scaling of the plate heat exchanger.
Replace – rinse out.
Defective temperature sensors
.
Check – replace.
Defective controller.
Check – replace.
Hot water in some taps but not in all.
DCW is being mixed with the DHW,
Check – replace.
DHW circulation pump out of order
or with too low setting. (Only if DHW
circulation is installed)
Replace - clean
Tap temperature too high; DHW tap load
too high.
Defective temperature sensors
.
Check – replace.
Temperature drop during tapping.
Scaling of the plate heat exchanger.
Replace – rinse out.
Larger DHW flow than the station has
been designed for.
Reduce DHW flow.
Mounting and installation guide
EvoFlat WSS Water Heaters
