S
sai_2
Hi,
I have a central heating system that has been causing me no end of problems. It was installed 5 years ago. A new Potterton Suprima 30, four new radiators and a hot water cylinder.
The cylinder is connected up like a radiator using a tapstat, so that when the water in there is hot, it closes the valve and there is return pipe that sends the water back, bypassing the cylinder completely.
Original problem
It took 3-4 hours or more to heat up a cylinder of water (big problem) and the rads weren't getting hot enough. Occasionally the boiler tripped out, so that you were guaranteed a lovely cold shower in the morning
Solution
Automatic air-release type valve fitted to the cylinder. That seemed to fix the 3-4 hour problem. Full cylinder of water now in just 45 minutes.
Rad problem
So the rads weren't all getting hot enough still. Each one was evenly hot (i.e. no cold spots at top or bottom), but not hot enough to burn your hand.
Occasionally, they did get super hot, but this was a rare thing.
The first one of the four rads in the series was normally the most consistent in terms of heat. This is a large towel-radiator in the bath room. I did expiriment with turning that one down a bit and this seemed to help balance the system somewhat, but it was still quite rare for all of them to get hot as the boiler never burned for long enough. It comes on, heats some water an then flashes green for a few minutes before burning some more. Occasionally, it would trip out, but this was quite rare, e.g. once a month or so.
Anyway, it started tripping out more frequently, so BG came round and turned the pump up to 3 (it was on 2 before). The engineer didn't check the PCB, so I don't know if this is at fault.
Immersion element
This was installed along with a new cylinder. The old cylinder didn't have an element and the slot couldn't be freed up, so a new cylinder was installed. The system was drained down (water was clean), cylinder and immersion fitted and refilled. Immersion checked and working great.
However, now there were some strange scraping noises coming from some of the pipes when the boiler came on (after a couple of minutes), followed by a pretty scary series of banging sounds, followed by the boiler cutting off (all within a few minutes). I did notice that there was some air in the system, which I managed to bleed from the rads, but this didn't help.
BG came round and installed a new pump. Apparently, the old one had failed. They installed a BG branded one and it has been left on 3. Now nothing works. The boiler comes on for about a minute and then goes off. After a few goes, it trips out and needs a reset. One of the pipes from the boiler is very hot at this stage and the other one is cool. There are no banging or scraping noises at all now. The pump sounds like it is doing its job.
That is pretty much where I am now. BG came around again and said that there is no circulation at all and the system needs a flush due to sludge. Does that sound correct? Or is the problem with the Potterton? Any suggestions would be very welcomed.
I did wonder if there could be sludge in the system if only 3 weeks ago, the whole system was drained and the water was clean? I did speak to the plumber that did that job and he has 30 years' experience and he thinks that sludge is definitely not an issue. Also, the rads have never had cold spots at the bottoms (very occasionally at the top due to air though).
A few other things that may be relevant:
There is no room thermostat anywhere. The rads each have a thermostatic control on them (except the first one).
Because of the way that the system is set up, the timer only used the "heating advance" side. The "hot water advance" is redundant. So if you want hot water and no heating, you just turn the rads off. Silly I know, but it seems to work, when it works.
Thanks in advance.[/b]
I have a central heating system that has been causing me no end of problems. It was installed 5 years ago. A new Potterton Suprima 30, four new radiators and a hot water cylinder.
The cylinder is connected up like a radiator using a tapstat, so that when the water in there is hot, it closes the valve and there is return pipe that sends the water back, bypassing the cylinder completely.
Original problem
It took 3-4 hours or more to heat up a cylinder of water (big problem) and the rads weren't getting hot enough. Occasionally the boiler tripped out, so that you were guaranteed a lovely cold shower in the morning
Solution
Automatic air-release type valve fitted to the cylinder. That seemed to fix the 3-4 hour problem. Full cylinder of water now in just 45 minutes.
Rad problem
So the rads weren't all getting hot enough still. Each one was evenly hot (i.e. no cold spots at top or bottom), but not hot enough to burn your hand.
Occasionally, they did get super hot, but this was a rare thing.
The first one of the four rads in the series was normally the most consistent in terms of heat. This is a large towel-radiator in the bath room. I did expiriment with turning that one down a bit and this seemed to help balance the system somewhat, but it was still quite rare for all of them to get hot as the boiler never burned for long enough. It comes on, heats some water an then flashes green for a few minutes before burning some more. Occasionally, it would trip out, but this was quite rare, e.g. once a month or so.
Anyway, it started tripping out more frequently, so BG came round and turned the pump up to 3 (it was on 2 before). The engineer didn't check the PCB, so I don't know if this is at fault.
Immersion element
This was installed along with a new cylinder. The old cylinder didn't have an element and the slot couldn't be freed up, so a new cylinder was installed. The system was drained down (water was clean), cylinder and immersion fitted and refilled. Immersion checked and working great.
However, now there were some strange scraping noises coming from some of the pipes when the boiler came on (after a couple of minutes), followed by a pretty scary series of banging sounds, followed by the boiler cutting off (all within a few minutes). I did notice that there was some air in the system, which I managed to bleed from the rads, but this didn't help.
BG came round and installed a new pump. Apparently, the old one had failed. They installed a BG branded one and it has been left on 3. Now nothing works. The boiler comes on for about a minute and then goes off. After a few goes, it trips out and needs a reset. One of the pipes from the boiler is very hot at this stage and the other one is cool. There are no banging or scraping noises at all now. The pump sounds like it is doing its job.
That is pretty much where I am now. BG came around again and said that there is no circulation at all and the system needs a flush due to sludge. Does that sound correct? Or is the problem with the Potterton? Any suggestions would be very welcomed.
I did wonder if there could be sludge in the system if only 3 weeks ago, the whole system was drained and the water was clean? I did speak to the plumber that did that job and he has 30 years' experience and he thinks that sludge is definitely not an issue. Also, the rads have never had cold spots at the bottoms (very occasionally at the top due to air though).
A few other things that may be relevant:
There is no room thermostat anywhere. The rads each have a thermostatic control on them (except the first one).
Because of the way that the system is set up, the timer only used the "heating advance" side. The "hot water advance" is redundant. So if you want hot water and no heating, you just turn the rads off. Silly I know, but it seems to work, when it works.
Thanks in advance.[/b]