Hello to all
I've got a problem that began to occur yesterday, but sees to be slightly different (I think) to some others that appear similar on the forum.
We have a four bedroom house. The Stelrad boiler and Grundfos pump are out in the garage. The pump sits just above the boiler. The Potterton timer and Honeywell diverter valve are both in the upstairs airing cupboard along with the hot water cylinder tank. There is a single thermostat in the downstairs hall.
From yesterday, all of the radiators downstairs have not been heating up. Indeed, as of yesterday evening, none of the radiators anywhere were heating up at all. My first step was to bleed all of the radiators.
All of the upstairs radiators (4x bedrooms and 2x bathrooms) had air in them, and this has now been expelled. None of the downstairs rads had any air in them, with water leaking out of the check valves immediately upon opening them.
I turned the heating on and fiddled with the silver lever on the bottom of the diverter valve. Eventually, and after much fiddling, I managed to get some heat appearing in the upstairs rads, and these are now getting "very warm" if not quite "boiling hot" as before.
I can see that the boiler is on and firing. It appears to be working ok. After taking hot water our of the taps, I could see that the boiler was coming on and heating water and then going off again.
The Grunfos pump by the boiler however is getting extremely hot indeed. It was scalding to the touch. The last time this happened, about two years ago, it turned out to be the Honeywell diverter valve that had packed up, and this was replaced with a brand new unit and has been working perfectly ever since. As it happens, a brand new Potterton timer was also fitted at the same time, as I had incorrectly diagnosed this as the fault. This is why I was fiddling primarily with the diverter valve last night, as it seemed to be the same thing happening over again. The diverter valve is now set back as it should be with the small silver lever set to "auto".
This morning, the rads came on, but only upstairs again. All of the rads downstairs were icy cold.
From searching other similar reports of similar problems, the advice seems to be to turn off the rads that are working and force the pressure onto the ones that aren't, and to expect the rads nearest the boiler to heat up first - this is the thing. The radiators in the hall and lounge are the nearest to the boiler, and to be fair, when the system is working properly, these are the first to heat up. However, they're just not. This is what I don't understand, but I am guessing that the pipes from the boiler/pump in the garage, actually lead upstairs and directly to the airing cupboard as the first port of call. I can see that the pipes leading away from the boiler, feed into the roof of the garage and then enter the house at about "upstairs ground level". I am guessing that the pipes feed under the floor of the 1st floor, and then pop up through the floor of the airing cupboard hitting the diverter valve first, then either entering the hot water tank or the central heating system. This leads me to conclude that the rads that should be heating up first are in fact the upstairs rads, and then reliant on a part gravity / part pump pressure to feed the hot water round the rest of the system to get round the rest of the house and, in particular, the downstairs rads?
Checking the hot water pipes coming out of the diverter valve, when the CH is on on the programmer, they're all really, really hot - both going to the hot water tank, and the other two which must be the central heating pipes. Therefore, the hot water must be making it up the system from the boiler, being pumped upto the airing cupboard to get this far into the system.
This is why I suspect the most likely candidate at the moment is some sort of air blockage or air lock? I'm continuing to bleed the rads, but there's no more air coming out of any of them at the moment... Gggggrrrrrrr
I am also concerned about the temperature of the pump, which shouldn't be getting this hot - it's clearly overworking, or stuck or broken or something - I know that it just shouldn't get this damn hot. However, I've now reached the limits of my knowledge about what to do next, or what really is the root cause of the problem actually is?
Also, normally, when you press the CH button the programmer to override its set times and bring the CH on, there is a "click", a bit of gurgling, and then a flow of water (that you can hear in / around the airing cupboard) and you can hear the flow of water. At the moment, there is nothing, so I am concerned that it might be the pump that is either kaput, or close to kaput?
Finally, I have just checked the CH expansion tank in the loft. This seems to be exactly as it should be, is 3/4's full and at the same white "limescale" line around the inside of the tank as it clearly has been for years.
I would be really, really grateful for any advice/pointers to help me diagnose and fix the problem.
Many thanks in advance for any replies.
I've got a problem that began to occur yesterday, but sees to be slightly different (I think) to some others that appear similar on the forum.
We have a four bedroom house. The Stelrad boiler and Grundfos pump are out in the garage. The pump sits just above the boiler. The Potterton timer and Honeywell diverter valve are both in the upstairs airing cupboard along with the hot water cylinder tank. There is a single thermostat in the downstairs hall.
From yesterday, all of the radiators downstairs have not been heating up. Indeed, as of yesterday evening, none of the radiators anywhere were heating up at all. My first step was to bleed all of the radiators.
All of the upstairs radiators (4x bedrooms and 2x bathrooms) had air in them, and this has now been expelled. None of the downstairs rads had any air in them, with water leaking out of the check valves immediately upon opening them.
I turned the heating on and fiddled with the silver lever on the bottom of the diverter valve. Eventually, and after much fiddling, I managed to get some heat appearing in the upstairs rads, and these are now getting "very warm" if not quite "boiling hot" as before.
I can see that the boiler is on and firing. It appears to be working ok. After taking hot water our of the taps, I could see that the boiler was coming on and heating water and then going off again.
The Grunfos pump by the boiler however is getting extremely hot indeed. It was scalding to the touch. The last time this happened, about two years ago, it turned out to be the Honeywell diverter valve that had packed up, and this was replaced with a brand new unit and has been working perfectly ever since. As it happens, a brand new Potterton timer was also fitted at the same time, as I had incorrectly diagnosed this as the fault. This is why I was fiddling primarily with the diverter valve last night, as it seemed to be the same thing happening over again. The diverter valve is now set back as it should be with the small silver lever set to "auto".
This morning, the rads came on, but only upstairs again. All of the rads downstairs were icy cold.
From searching other similar reports of similar problems, the advice seems to be to turn off the rads that are working and force the pressure onto the ones that aren't, and to expect the rads nearest the boiler to heat up first - this is the thing. The radiators in the hall and lounge are the nearest to the boiler, and to be fair, when the system is working properly, these are the first to heat up. However, they're just not. This is what I don't understand, but I am guessing that the pipes from the boiler/pump in the garage, actually lead upstairs and directly to the airing cupboard as the first port of call. I can see that the pipes leading away from the boiler, feed into the roof of the garage and then enter the house at about "upstairs ground level". I am guessing that the pipes feed under the floor of the 1st floor, and then pop up through the floor of the airing cupboard hitting the diverter valve first, then either entering the hot water tank or the central heating system. This leads me to conclude that the rads that should be heating up first are in fact the upstairs rads, and then reliant on a part gravity / part pump pressure to feed the hot water round the rest of the system to get round the rest of the house and, in particular, the downstairs rads?
Checking the hot water pipes coming out of the diverter valve, when the CH is on on the programmer, they're all really, really hot - both going to the hot water tank, and the other two which must be the central heating pipes. Therefore, the hot water must be making it up the system from the boiler, being pumped upto the airing cupboard to get this far into the system.
This is why I suspect the most likely candidate at the moment is some sort of air blockage or air lock? I'm continuing to bleed the rads, but there's no more air coming out of any of them at the moment... Gggggrrrrrrr
I am also concerned about the temperature of the pump, which shouldn't be getting this hot - it's clearly overworking, or stuck or broken or something - I know that it just shouldn't get this damn hot. However, I've now reached the limits of my knowledge about what to do next, or what really is the root cause of the problem actually is?
Also, normally, when you press the CH button the programmer to override its set times and bring the CH on, there is a "click", a bit of gurgling, and then a flow of water (that you can hear in / around the airing cupboard) and you can hear the flow of water. At the moment, there is nothing, so I am concerned that it might be the pump that is either kaput, or close to kaput?
Finally, I have just checked the CH expansion tank in the loft. This seems to be exactly as it should be, is 3/4's full and at the same white "limescale" line around the inside of the tank as it clearly has been for years.
I would be really, really grateful for any advice/pointers to help me diagnose and fix the problem.
Many thanks in advance for any replies.