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Hi!
So, I'm trying to help my dear ol' Ma with her heating woes.
The Setup:
She has a Potterton Profile boiler in a gravity fed S type hot water / CH system.
There are two Danfoss HPA2 2 port valves.
The CH one is just above the boiler, on the left(outflow I believe) pipe - that pipe forks, one side to, I would presume, the hot water cylinder, the other to this port. The return / right hand side pipe has the pump. There is no thermostat, although she is rather frugal when it comes to leaving radiators on or the boiler dial high (I will be convincing her to get a Nest, because I like gadgets, even though I live 200 miles away) - The hot water system has a thermostat - set at around 50 deg - and another Danfoss HPA2 2 port valve.
"Interesting" Sidenote:
As a sidenote, my Ma has had the hot water on 24/7 for quite a number of years. I'm telling her that I don't think that's actually what she needs especially as she is the only one who really lives there, despite weekly visits from her children that stay and shower in the morning. She claims the heating engineer that put it in said it was most efficient that way.
The Problem:
So.. the initial issue was that upstairs bathroom towel radiator would always be hot no matter what, and the downstairs rads would be lukewarm with the heating on or off.
My first port of call (pun intended) was the two port valve above the boiler, I switched this to manual. The rads then would not go off and were really rather hot! Switching the CH off, the manual switch on the valve was not moving back across. So I removed the actuator and found the tap was stuck stiff. Also there was a lot of corrosion around this tap and plate. Using pliers and WD40 I managed to loosen the tap and the CH mostly went off. However, the bathroom and pipes down to a hallway rad (the pipe returns immediately back into the ceiling from the other side of the rad so hard to say where it is on the circuit) remain piping hot.
To further try and diagnose the system, I left the actuator off the CH valve, left the boiler switched off for some time to cool the pipes down. I then ensured the valve was closed (horizontal tap) and turned the hot water on. The outflow pipe soon became very hot, the pipe into the valve was also obviously very hot, but the pipe out the top stayed cool until shortly after becoming similarly hot.
The Question:
Could this be a balance issue and the return from the hot water is coming back through the CH pipes instead of the boiler return?
Could the corroded 2 port valve be similarly faulty inside and allowing hot water flow but at a limited capacity and need replacing even more immediately?
Final Sidenote/question:
When the hot water is on, the boiler does switch off when (and I should investigate this further but while I'm here writing an essay) I presume the temperature is reached in the cylinder, but the pump seems to continue whining the whole time.
Can I confirm that the pump should only be on if either of the actuators are switched on, and not just because the programmer has the hot water program on? Or the whole time the hot water is on, the pump should keep the water flowing through the cylinder?
Thank you if you even bothered reading this monolog, and thanks even more if you can help point me in the right directions or even confirm my thinking.
So, I'm trying to help my dear ol' Ma with her heating woes.
The Setup:
She has a Potterton Profile boiler in a gravity fed S type hot water / CH system.
There are two Danfoss HPA2 2 port valves.
The CH one is just above the boiler, on the left(outflow I believe) pipe - that pipe forks, one side to, I would presume, the hot water cylinder, the other to this port. The return / right hand side pipe has the pump. There is no thermostat, although she is rather frugal when it comes to leaving radiators on or the boiler dial high (I will be convincing her to get a Nest, because I like gadgets, even though I live 200 miles away) - The hot water system has a thermostat - set at around 50 deg - and another Danfoss HPA2 2 port valve.
"Interesting" Sidenote:
As a sidenote, my Ma has had the hot water on 24/7 for quite a number of years. I'm telling her that I don't think that's actually what she needs especially as she is the only one who really lives there, despite weekly visits from her children that stay and shower in the morning. She claims the heating engineer that put it in said it was most efficient that way.
The Problem:
So.. the initial issue was that upstairs bathroom towel radiator would always be hot no matter what, and the downstairs rads would be lukewarm with the heating on or off.
My first port of call (pun intended) was the two port valve above the boiler, I switched this to manual. The rads then would not go off and were really rather hot! Switching the CH off, the manual switch on the valve was not moving back across. So I removed the actuator and found the tap was stuck stiff. Also there was a lot of corrosion around this tap and plate. Using pliers and WD40 I managed to loosen the tap and the CH mostly went off. However, the bathroom and pipes down to a hallway rad (the pipe returns immediately back into the ceiling from the other side of the rad so hard to say where it is on the circuit) remain piping hot.
To further try and diagnose the system, I left the actuator off the CH valve, left the boiler switched off for some time to cool the pipes down. I then ensured the valve was closed (horizontal tap) and turned the hot water on. The outflow pipe soon became very hot, the pipe into the valve was also obviously very hot, but the pipe out the top stayed cool until shortly after becoming similarly hot.
The Question:
Could this be a balance issue and the return from the hot water is coming back through the CH pipes instead of the boiler return?
Could the corroded 2 port valve be similarly faulty inside and allowing hot water flow but at a limited capacity and need replacing even more immediately?
Final Sidenote/question:
When the hot water is on, the boiler does switch off when (and I should investigate this further but while I'm here writing an essay) I presume the temperature is reached in the cylinder, but the pump seems to continue whining the whole time.
Can I confirm that the pump should only be on if either of the actuators are switched on, and not just because the programmer has the hot water program on? Or the whole time the hot water is on, the pump should keep the water flowing through the cylinder?
Thank you if you even bothered reading this monolog, and thanks even more if you can help point me in the right directions or even confirm my thinking.