My air source heat pump is mounted on the wall outside about 3 metres up. The flow comes in at ceiling level, down to a diverter valve that chooses DHW or UFH. In DHW mode it runs round s coil in the adjacent tank and returns. In UFH the flow drops to ground floor level and splits, one to ground floor UFH manifold, the other way up to the manifold on the first floor.
Both the manifolds have Auto bleed valves on them, and are less than a year old. Occasionally a fault of no flow/no water in the circulator is logger by the heat pump. I'm able to get things running again by leaving the system to sit in a fully inactive state for a while (overnight) then opening all UFH circuits and setting both UFH pumps on max (they're normally on 1-2 out of 7) and power cycling the heat pump. A long sequence of gurgling and whooshing noises and the fault normally clears. I think it's fair bet that the pump in the HP got air locked and the UFH pumps were enough to drag fluid through, but this system has been in constant op for at least 6 months so I was hoping there wouldn't be much air left. The manual bleed points I have available never have any air in them. I don't know if there is s bleed valve in the pump itself and I have a concern that it's naturally a high point in the system because of how its plumbed (the DHW diverter being lower means air in the HP wouldn't naturally drift into the upstairs UFH circuits?) so ultimately I'm wondering how to get the blenders I have to expunge the air I have- do they work if the pumps are pumping fluid constantly or do auto blessed need periods of inactivity in the system to allow bubbles to write into them and not get pumped past them?
Both the manifolds have Auto bleed valves on them, and are less than a year old. Occasionally a fault of no flow/no water in the circulator is logger by the heat pump. I'm able to get things running again by leaving the system to sit in a fully inactive state for a while (overnight) then opening all UFH circuits and setting both UFH pumps on max (they're normally on 1-2 out of 7) and power cycling the heat pump. A long sequence of gurgling and whooshing noises and the fault normally clears. I think it's fair bet that the pump in the HP got air locked and the UFH pumps were enough to drag fluid through, but this system has been in constant op for at least 6 months so I was hoping there wouldn't be much air left. The manual bleed points I have available never have any air in them. I don't know if there is s bleed valve in the pump itself and I have a concern that it's naturally a high point in the system because of how its plumbed (the DHW diverter being lower means air in the HP wouldn't naturally drift into the upstairs UFH circuits?) so ultimately I'm wondering how to get the blenders I have to expunge the air I have- do they work if the pumps are pumping fluid constantly or do auto blessed need periods of inactivity in the system to allow bubbles to write into them and not get pumped past them?
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