S
Sam Grocock
Hi guys, we moved into a place last Dec with an old Grant Euroflame oil boiler with 4 pipes, one set with a Grundfos pump on it and the other set running upstairs to a HW cylinder. We've never been able to get HW generated from the boiler for a sustained period, the water doesn't seem to flow that side at all.
Early this year I was having to regularly bleed the pump (which was 20 years old+) as the CH would get stuck and only come back after bleeding air from the old pump. I figured the pump was on its way out. A month ago I went to switch it on after it being off all summer and it wouldn't budge at all so we fitted a new UPS3 and it worked faultlessly for 2 weeks.
Then I partially drained the system down to add inhibitor, topped back up and since then after ~20mins of boiler+pump being on (doesn't happen if just the pump is running without the boiler.. even if the CH water is still running hot) there's a wooshing/gurgling noise and the pump will sound strained and the rads just cut off, no circulation. The pump goes dead quiet but still struggling doing something.
I've bled all the rads and there's no more air that I can get out, after getting some initially after the system was topped back up. When the block happens I have to turn the pump off and on for 5-10mins which is noisy (like bubbles going through it) and gets something moving and then the system will work for 10-20mins again. I've tried to bleed the rads closest to the boiler after the system is unblocked though, can't get anything out of them except water (which is clear, no sludge coming out). It's odd that the system was working just fine for weeks until I drained and topped it up.
Anyone with any similar issues in the past? Been wracking my brain for weeks to figure this out. Cheers.
Early this year I was having to regularly bleed the pump (which was 20 years old+) as the CH would get stuck and only come back after bleeding air from the old pump. I figured the pump was on its way out. A month ago I went to switch it on after it being off all summer and it wouldn't budge at all so we fitted a new UPS3 and it worked faultlessly for 2 weeks.
Then I partially drained the system down to add inhibitor, topped back up and since then after ~20mins of boiler+pump being on (doesn't happen if just the pump is running without the boiler.. even if the CH water is still running hot) there's a wooshing/gurgling noise and the pump will sound strained and the rads just cut off, no circulation. The pump goes dead quiet but still struggling doing something.
I've bled all the rads and there's no more air that I can get out, after getting some initially after the system was topped back up. When the block happens I have to turn the pump off and on for 5-10mins which is noisy (like bubbles going through it) and gets something moving and then the system will work for 10-20mins again. I've tried to bleed the rads closest to the boiler after the system is unblocked though, can't get anything out of them except water (which is clear, no sludge coming out). It's odd that the system was working just fine for weeks until I drained and topped it up.
Anyone with any similar issues in the past? Been wracking my brain for weeks to figure this out. Cheers.
