Hi All,
First post here and I'm hoping for some assistance to quell my worries and let me have a good night sleep.
Before I start, I would state that I'm neither a plumber nor a plumbing expert, but I do my research where I can so I understand issues.
I have a pressurised heating system, consisting of a Megaflo CL250 cylinder. I had an old Grundfos UPE 25-80 circulating pump, which two months ago the bearings failed. I spoke to a local pump supplier, who recommended a like-for-like replacement to a UPS2 25-80 pump, which has now been installed by a plumber. I had initial concerns about installing this light-commercial pump, as the pump is for my house. However, the pump suppliers recommended this pump was suitable given my house has 18 radiators.
Since the new pump has been fitted, we have experienced all sorts of noises and bangs emanating from the pump. I have bled the radiators multiple times, and each time have only managed to expel a small amount of air (1-2 seconds of ‘hissing’ on 2-3 radiators). There is also an auto air vent above the pump. The current ‘noise situation’ is that the pump makes a bang when it starts up (either when the heating or hot water valves open), this is a short bang, probably half-a-second in duration but it is quite loud. Our heating comes on early morning, and the sound is loud enough to wake us. When the CH valve is open, the pump (now) runs quietly, though it did make the occasional grinding noise. I hope this was just air in the system after it being replaced. However, a new issue which has arisen in the past couple of days is that when the HW valve only is open, the pump makes a permanently grinding noise. This only occurs on the lowest speed setting, the middle and highest speed settings do not result in this sound. However, the higher pump speeds produced a louder bang than the lowest speed setting, so it’s a lose-lose situation at the moment.
With the old pump, we never experienced these issues, so I cannot understand why and like-for-like (albeit updated) replacement would cause these problems.
As a side issue, we have experienced low hot water pressure. When fitting the pump we asked the plumber for his opinion on this. He originally thought the pressure reducing valve on the cylinder inlet was blocked (the original installer of the system had placed the limefighter after the PRV – even I can see the problem with this!). We agreed therefore to have the PRV replaced, but when the plumber came to do this, we had issues with draining the cylinder. The first time the plumber attempted it, the (250L) cylinder appeared to drain in 2 minutes. The plumber then discovered he had been given the incorrect part, so had to return the next day. When he did and drained the system again, the cylinder took about 10 minutes to drain. However, despite opening the lowest hot water tap we could hear a continual bubbling. The plumber thought the heating coil in the cylinder might be cracked, which could therefore result in the noise in the pump and the low water pressure.
He therefore suggested changing the cylinder, which is a much greater expense than the work originally envisaged.
I would also add that plumber did clean out the PRV when draining the cylinder, and now the water pressure does appear to be better. Also, around Christmas, I attempted to recharged the cylinder according to the instructions on the side of the cylinder. I did this twice in the space of a week, and each time it took about 5 minutes to fill the air pocket.
I am happy to have whatever work is needed to fix the system, but I am honestly confused as to what the true issue is.
I appreciate the above is a bit of a ramble, but if anyone could figure out what my underlying issue is from my description, I would be most grateful.
Thank you all in advance.
First post here and I'm hoping for some assistance to quell my worries and let me have a good night sleep.
Before I start, I would state that I'm neither a plumber nor a plumbing expert, but I do my research where I can so I understand issues.
I have a pressurised heating system, consisting of a Megaflo CL250 cylinder. I had an old Grundfos UPE 25-80 circulating pump, which two months ago the bearings failed. I spoke to a local pump supplier, who recommended a like-for-like replacement to a UPS2 25-80 pump, which has now been installed by a plumber. I had initial concerns about installing this light-commercial pump, as the pump is for my house. However, the pump suppliers recommended this pump was suitable given my house has 18 radiators.
Since the new pump has been fitted, we have experienced all sorts of noises and bangs emanating from the pump. I have bled the radiators multiple times, and each time have only managed to expel a small amount of air (1-2 seconds of ‘hissing’ on 2-3 radiators). There is also an auto air vent above the pump. The current ‘noise situation’ is that the pump makes a bang when it starts up (either when the heating or hot water valves open), this is a short bang, probably half-a-second in duration but it is quite loud. Our heating comes on early morning, and the sound is loud enough to wake us. When the CH valve is open, the pump (now) runs quietly, though it did make the occasional grinding noise. I hope this was just air in the system after it being replaced. However, a new issue which has arisen in the past couple of days is that when the HW valve only is open, the pump makes a permanently grinding noise. This only occurs on the lowest speed setting, the middle and highest speed settings do not result in this sound. However, the higher pump speeds produced a louder bang than the lowest speed setting, so it’s a lose-lose situation at the moment.
With the old pump, we never experienced these issues, so I cannot understand why and like-for-like (albeit updated) replacement would cause these problems.
As a side issue, we have experienced low hot water pressure. When fitting the pump we asked the plumber for his opinion on this. He originally thought the pressure reducing valve on the cylinder inlet was blocked (the original installer of the system had placed the limefighter after the PRV – even I can see the problem with this!). We agreed therefore to have the PRV replaced, but when the plumber came to do this, we had issues with draining the cylinder. The first time the plumber attempted it, the (250L) cylinder appeared to drain in 2 minutes. The plumber then discovered he had been given the incorrect part, so had to return the next day. When he did and drained the system again, the cylinder took about 10 minutes to drain. However, despite opening the lowest hot water tap we could hear a continual bubbling. The plumber thought the heating coil in the cylinder might be cracked, which could therefore result in the noise in the pump and the low water pressure.
He therefore suggested changing the cylinder, which is a much greater expense than the work originally envisaged.
I would also add that plumber did clean out the PRV when draining the cylinder, and now the water pressure does appear to be better. Also, around Christmas, I attempted to recharged the cylinder according to the instructions on the side of the cylinder. I did this twice in the space of a week, and each time it took about 5 minutes to fill the air pocket.
I am happy to have whatever work is needed to fix the system, but I am honestly confused as to what the true issue is.
I appreciate the above is a bit of a ramble, but if anyone could figure out what my underlying issue is from my description, I would be most grateful.
Thank you all in advance.
