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Could someone please help me identify the issue with water filled underfloor heating system which seems to be circulating water through all pipes on the manifold but the water being circulated is cold even though pipes that come out from boiler and connected to the UFH system are very hot.
Here are pictures of the system:
(more pictures of the whole boiler setup below - really don't understand why there is also a water tank if it is a sealed system - both pipes going to and from the tank seem to be just connected to the same supply pipe coming out of the boiler - what is the purpose of this?
can anyone understand how this whole thing supposed to work?)
I had expensive local plumbing company looking at it, they flushed all pipes with an external pump to make sure there is no air in the manifold but it didn't help at all.
When the Grundfos pump is running I could see all flow meters showing steady 1-2 L/min flow in all sections, however, it seems to be just pumping cold water around.
Both top and bottom pipes to the right of that valve with red head are very hot but none of the hot water seems to be getting into the manifold connected to the left of the pump on those pictures. The only non-standard configuration here seems to be that the pump is about 5 meters away from where the actual manifold begins i.e. the top picture and the one below are in different rooms.
So, the question is what's wrong here - could it be that the mixing valve is faulty or something is not right with that Honeywell thermo-switch connecting top and bottom pipes from the boiler (I already tried removing it completely with no effect)? or is it something else entirely?
Thank you to anyone who could explain in details how this is supposed to work anyway i.e., how is the hot water supposed to get into the manifold at all and what could prevent it from doing this.
Here are pictures of the system:
(more pictures of the whole boiler setup below - really don't understand why there is also a water tank if it is a sealed system - both pipes going to and from the tank seem to be just connected to the same supply pipe coming out of the boiler - what is the purpose of this?
can anyone understand how this whole thing supposed to work?)
I had expensive local plumbing company looking at it, they flushed all pipes with an external pump to make sure there is no air in the manifold but it didn't help at all.
When the Grundfos pump is running I could see all flow meters showing steady 1-2 L/min flow in all sections, however, it seems to be just pumping cold water around.
Both top and bottom pipes to the right of that valve with red head are very hot but none of the hot water seems to be getting into the manifold connected to the left of the pump on those pictures. The only non-standard configuration here seems to be that the pump is about 5 meters away from where the actual manifold begins i.e. the top picture and the one below are in different rooms.
So, the question is what's wrong here - could it be that the mixing valve is faulty or something is not right with that Honeywell thermo-switch connecting top and bottom pipes from the boiler (I already tried removing it completely with no effect)? or is it something else entirely?
Thank you to anyone who could explain in details how this is supposed to work anyway i.e., how is the hot water supposed to get into the manifold at all and what could prevent it from doing this.
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