4.2 Start-up
Start-up, Heating with mixing loop
Start-up:
1: Pump speed
Set the pump to highest speed before start-up.
2: Start pump
Start the pump and heat through the system.
3: Open shut-off valves
The shut-off valves should then be opened and the unit observed
as it enters service. Visual checking should confirm temperatures,
pressures, acceptable thermal expansion and absence of leakage.
If the system operates in accordance with design, it can be put
to regular use.
4: Vent system
Switch off the pump and vent the installation after the radiators
have been warmed up.
5: Adjust pump speed
Set the pump to the lowest speed consistent with comfort and
electricity consumption.
Normally the change-over switch is set in the mid position (default).
However for systems with under floor heating or single pipe loop
systems, it may be necessary to turn the change-over switch
upwards.
Higher pump speeds are only used if the heating requirement
increases.
Re-thighten connections
After water has been added to the system and the system has been
put into operation, re-tighten
ALL
connections.
Pump
The pump must be switched off during system fill.
Under floor heating:
Pump stop function
If the substation is used in connection with under floor heating, the
circulation pump must be connected to the pump stop function in
the under floor heating controller. The pump must be stopped if
all under floor heating circuits are closed.
Warranty
If this is not possible, then flow must be continued through the
by-pass. Failing this, the pump will be at risk of seizure and any
remaining warranty will be withdrawn.
Summer operation:
Switch off pump
In summer the circulation pump must be switched off and the
shut-off valve to HE supply closed.
Running pump bi-weekly
It is recommended to start up the circulation pump (for 2 minutes)
once a month during summer; the shut-off valve of the HE supply
must be shut.
Electronic controller
Most electronic controllers will start up the pump automatically
(please note manufacturer´s instructions).
6 | © Danfoss | 2019.01
VI.CW.Y5.02 / LUK42260
Operating Guide Termix VMTD MIX Compact 28
