Danfoss EvoFlat 4.0 Guide D'installation page 14

Installation Guide
8. TROUBLESHOOTING
8.1 Troubleshooting in general
In the event of operating disturbances, the following basic features
should be checked before carrying out actual troubleshooting:
• the flat station is connected to electricity,
• the strainer 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.
8.2 Troubleshooting: DHW
Problem
Too little or no domestic hot
water
DHW is available only at some
draw-off points.
DHW temperature too high
Temperature drop during
tapping.
14 | © Danfoss | DCS-SGDPT/PL | 2022.01
EvoFlat 4.0 Flat Stations for apartments, single- and multi-family houses
Possible cause
Supply flow insufficient
Low temperature / variations in temperature at the
draw-off points
Strainer in the cold water supply line clogged.
Circulation pump out of operation , set at too low
speed of rotation (if DHW circulation is established)
Non-return valve defective or clogged
(if DHW circulation is established)
Defective DHW thermostat
Defective TPC-M controller
Calified heat exchanger
Lack of cold water pressure
Defective thermostatic mixing valve
DHW controller
DHW controller defective
Larger DHW flow than the flat station has been
designed for.
Authorized personnel only
Assembly, start-up and maintenance work
must be performed by qualified and authorized
personnel only.
Solution
Collect data from the heat meter
Check the network pump — constant pressure
If necessary, close the bypass in the tap block on
the bathroom radiator
Check the function of the ball valves and open
if necessary
Vent the system throughly — see the instruction
Change the summer bypass setting if
necessary
Collect data from the heat meter
Change the positioning time of the mixer actuator
Change the heating curve if necessary
Position the switch-on sensor correctly on the
buffer line
Change cleaning periods for biomass boilers
Clean strainer
Check the function of the circulation pump and
replace if required
Check the functioning of the non-return valve and
replace if required
Check the functioning of the DHW thermostat
and repace if necessary
Check the functions of the controller,
and replace if required
Replace heat exchanger
Increase pressure
Replace thermostatic mixing valve
Adjust controller
Check the functions of the controller,
and replace if required
Reduce DHW flow
AN40274706699301-010101