Too high DH return temperature.
Too small heating surface/too small
radiators compared to the total heating
requirement of the building.
Increase total heating surface.
Poor utilization of existing heating surface.
Defective sensor on self-acting thermostat.
Make sure the heat is distributed evenly
across the full heating surface – open all
radiators and keep the radiators in the
system from heating up at the bottom. It
is extremely important to keep the supply
temperature to the radiators as low as
possible, while maintaining a reasonable
level of comfort.
The system is single pipe loop.
The system should feature electronic
controls as well as return sensors.
Pump pressure too high.
Adjust pump to a lower level.
Air in system.
Vent the system.
Defective or incorrectly set radiator valve(s).
Single pipe loop systems require special
one-pipe radiator valves.
Check – set/replace.
Dirt in the motorized valve or in the
differential pressure controller.
Check – clean out.
Defective motorized valve, sensor or
automatic controller.
Check – replace.
Electronic controller not adjusted correctly.
Adjust according to instructions.
Noise in system.
Pump pressure too high.
Adjust pump to a lower level.
Heat load too high.
Defective motorized valve, sensor or
electronic controller.
Check – replace.
AQ221686472754en–010401 / LUK4030601
© Danfoss | 2022.11 | 21
Operating Guide Termix VX with complete insulation
