Hot water pump / plumbing help, please
Discussion
Hi all.
This is a request for some advice from the plumbers on here, please.
I have included a youtube link below to a video clip of my Hot Water/Central Heating pump / tank so that you can hear the sounds that it's making. Obviously atm only the hot water is on. When I have used a significant quantity of hot water and the boiler is on to heat the water again, then there is the noise on the video clip coming from the pump / tank area. Doesn't sound much on the clip, but it is really loud (enough to wake us up in the morning). (Please watch it with sound turned up). Thinking it was air in the system, I have bled the pump via the screw on the front and no air came out - only a dribble of water.
Please can any experts on here help. Pump is only 4 months old - old one didn't make anywhere near the same noise. It's a Grundfos 15-60. Changing the speed setting on the side (1-3) reduces the noise level a bit - it's on 3 now, but it's still there on 1 and 2 setting.
Noise doesn't happen when I've hardly used any hot water from before - so not much to replenish.
Hope all this makes sense and thanks in advance.
Cheers, Jon
link - http://www.youtube.com/watch?v=6jvDpQXwNcA
This is a request for some advice from the plumbers on here, please.
I have included a youtube link below to a video clip of my Hot Water/Central Heating pump / tank so that you can hear the sounds that it's making. Obviously atm only the hot water is on. When I have used a significant quantity of hot water and the boiler is on to heat the water again, then there is the noise on the video clip coming from the pump / tank area. Doesn't sound much on the clip, but it is really loud (enough to wake us up in the morning). (Please watch it with sound turned up). Thinking it was air in the system, I have bled the pump via the screw on the front and no air came out - only a dribble of water.
Please can any experts on here help. Pump is only 4 months old - old one didn't make anywhere near the same noise. It's a Grundfos 15-60. Changing the speed setting on the side (1-3) reduces the noise level a bit - it's on 3 now, but it's still there on 1 and 2 setting.
Noise doesn't happen when I've hardly used any hot water from before - so not much to replenish.
Hope all this makes sense and thanks in advance.
Cheers, Jon
link - http://www.youtube.com/watch?v=6jvDpQXwNcA
Sounds like air as said.
Is your system open vented into a header tank in the loft? Air should escape through this vent over time. Might help to turn on the heating and hot water to help it dissipate and run it like this for a day or two.
Also, you should have air vents (usually thumb vents) on all high points of pipework that can't naturally vent. You maybe also have the odd automatic bleed vent which you can undo, but shut when finished as these tend to let by.
If that fails, you can drag a lot of the air out from a drain off.
Is your system open vented into a header tank in the loft? Air should escape through this vent over time. Might help to turn on the heating and hot water to help it dissipate and run it like this for a day or two.
Also, you should have air vents (usually thumb vents) on all high points of pipework that can't naturally vent. You maybe also have the odd automatic bleed vent which you can undo, but shut when finished as these tend to let by.
If that fails, you can drag a lot of the air out from a drain off.
Guys - thanks so much for the replies. I'm sure that it is an open system - there's a big cold water tank in the loft (and a smaller one). If I go up and investigate this cold water tank, then what am I looking for inside to bleed? I'll have another look at the 3 port valve for a bleed screw.
Once again, cheers for the advice.
Jon
Once again, cheers for the advice.
Jon
JONSCZ said:
Guys - thanks so much for the replies. I'm sure that it is an open system - there's a big cold water tank in the loft (and a smaller one). If I go up and investigate this cold water tank, then what am I looking for inside to bleed? I'll have another look at the 3 port valve for a bleed screw.
Once again, cheers for the advice.
Jon
The smaller one will be the central heating cistern. For feed and expansion purposes. While you're up there, check that there is water in the cistern.Once again, cheers for the advice.
Jon
It'll (most probably depending on configuration) have a vent pipe which will go up past the cistern and crook over towards the tank ending roughly with the top of the cistern. This will naturally vent the air.
The 3 port valve won't have a bleed screw. But quite often you'll find a piece of 15mm pipe sticking up 6" from a pipe run with a thumb vent on it, or an automatic bleed vent, (see below pictures).

I suggest running both the hot water and the heating together for a while, maybe a day(?) and that should hopefully vent it for you to either the radiators or the feed and expansion cistern.
Gingerbread Man said:
Sounds like air as said.
Is your system open vented into a header tank in the loft? Air should escape through this vent over time. Might help to turn on the heating and hot water to help it dissipate and run it like this for a day or two.
Also, you should have air vents (usually thumb vents) on all high points of pipework that can't naturally vent. You maybe also have the odd automatic bleed vent which you can undo, but shut when finished as these tend to let by.
If that fails, you can drag a lot of the air out from a drain off.
^^^Is your system open vented into a header tank in the loft? Air should escape through this vent over time. Might help to turn on the heating and hot water to help it dissipate and run it like this for a day or two.
Also, you should have air vents (usually thumb vents) on all high points of pipework that can't naturally vent. You maybe also have the odd automatic bleed vent which you can undo, but shut when finished as these tend to let by.
If that fails, you can drag a lot of the air out from a drain off.
Wot he said.
Do you have any hot water heated towel rails? These are good as a bleed off point, but it took ages to bleed our system over a period of weeks on both the hot water & heating loops.
We ran ran the pump on max to get the air moving around the system.
PS: Your airing cupboard could have been ours before I replaced it all

EDIT: I see you have a Cobra rep - you didn't drive to Ruscombe/Hare Hatch a few weeks ago did you?
Edited by Smiler. on Saturday 20th August 13:04
David, many thanks for the explaination and pics - I'll check it out.
Smiler - Hare Hatch is on my 'regular route' for a blast - mines blue with white stripes (if so, it could well have been me on the way to the Hare Hatch garden centre for pet food!). If it was me, then I hope I was behaving myself.......!
Cheers for taking the time to reply, guys. Really helpful.
Jon
Smiler - Hare Hatch is on my 'regular route' for a blast - mines blue with white stripes (if so, it could well have been me on the way to the Hare Hatch garden centre for pet food!). If it was me, then I hope I was behaving myself.......!
Cheers for taking the time to reply, guys. Really helpful.
Jon
We have essentially the same system and we were having "kettling" problems where the water in the heating circuit boils and purges the steam/water out of the overflow pipe.
Your's almost sounds like kettling without the banging pipes (our pipes banged something crazy when it happened) as if the pipes were completely secure the water would rush up the overflow pipe and gush into the top tank with a similar sound to yours.
Our solution was to get a new thermostat and fit it in the boiler (not recommended (or legal) if you're inept, I can deal with much scarier gasses that domestic so I'm sure I'm OK but it's a bone of contention for many!) which fixed the problem as the heating circuit was overheating causing our problem.
It generally only happened when the hot water was on and not both together, I guess there wasn't enough energy to boil the circuit when it was heating all the rads.
Your's almost sounds like kettling without the banging pipes (our pipes banged something crazy when it happened) as if the pipes were completely secure the water would rush up the overflow pipe and gush into the top tank with a similar sound to yours.
Our solution was to get a new thermostat and fit it in the boiler (not recommended (or legal) if you're inept, I can deal with much scarier gasses that domestic so I'm sure I'm OK but it's a bone of contention for many!) which fixed the problem as the heating circuit was overheating causing our problem.
It generally only happened when the hot water was on and not both together, I guess there wasn't enough energy to boil the circuit when it was heating all the rads.
James - that sounds beyond my level of 'tinkering', but I'll bear that in mind, thanks. I have come across the term 'kettling' whilst googling the problem.
Smiler - give me a wave if you see me out and about again around there!
Update is that I have been in the loft and the expansion tank is full (to the ball cock level, anyway), but has a partial 'scummy - yellowy' layer of stuff floating (and just below surface) on top - not sure if that's from the chemicals that were recently added when we had the system drained to fit the new pump (few months back). There is indeed a plastic vent pipe that goes to the top of the cistern tank, but no 'sticking up pipe' with a vent on it that I can see. Otherwise, all looks ok up there - I'll go with the leaving the heating and water on for a day or so (Mrs. jonscz will be happy as she's always cold!).
Again, cheers.....
Jon
Smiler - give me a wave if you see me out and about again around there!
Update is that I have been in the loft and the expansion tank is full (to the ball cock level, anyway), but has a partial 'scummy - yellowy' layer of stuff floating (and just below surface) on top - not sure if that's from the chemicals that were recently added when we had the system drained to fit the new pump (few months back). There is indeed a plastic vent pipe that goes to the top of the cistern tank, but no 'sticking up pipe' with a vent on it that I can see. Otherwise, all looks ok up there - I'll go with the leaving the heating and water on for a day or so (Mrs. jonscz will be happy as she's always cold!).
Again, cheers.....
Jon
I reckon you have a blocked cold feed...
This would require draining the system, and cutting out & cleaning the connection between the 15mm feed from the header tank, into the system.
This could be at the boiler, or somewhere between the boiler & pump, on the flow pipe.
A short term fix is to back fill the system up the open vent, above the header tank.
This would require draining the system, and cutting out & cleaning the connection between the 15mm feed from the header tank, into the system.
This could be at the boiler, or somewhere between the boiler & pump, on the flow pipe.
A short term fix is to back fill the system up the open vent, above the header tank.
Hi David. Yes, the valve is open. I am going to try leaving the heating/hot water on all day tomorrow or Wednesday, as you kindly advised, to see if that does it.
Also, Smiler - that is really good of you to offer the advice. I am not all that local unfortunately - it's just that Hare Hatch is on my regular 'Cobra' route when I need specialist pet food from the garden centre. As I said before, keep an eye open for the car and if I see a Monaro or 'lairy bike' then I'll know it's you!!!
I'll see what happens when I have left the system on for a while.
Cheers,
Jon
Also, Smiler - that is really good of you to offer the advice. I am not all that local unfortunately - it's just that Hare Hatch is on my regular 'Cobra' route when I need specialist pet food from the garden centre. As I said before, keep an eye open for the car and if I see a Monaro or 'lairy bike' then I'll know it's you!!!
I'll see what happens when I have left the system on for a while.
Cheers,
Jon

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