I've got a Grundfos 15-50 pump. Is it normal to be able to hear the water 'whooshing' around the pump when it is in operation? Mine makes the noise as soon as it is switched on, so I don't think it's the water boiling or kettling (is that more of a whistle?). The pump seems to be working fine, with HW and CH working as expected, I'm just concerned about the gurgling/pumping water noise.
Grundfos Pump Noise
- Thread starter Alfie25
- Start date
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For starters, crack open the large screw in the pump centre....this will let any air out thats present....you won't get a flood!
John
John
Hello, thanks I tried that already - unscrewed it by about 2 full turns and I could hear no air escaping but I very soon got dribbles of water coming out. Anything else I can try?
I'm guessing the noise isn't too normal?
I'm guessing the noise isn't too normal?
Circulating pumps are pretty quiet usually, although they can whine a bit when they are getting on.
Is there any air at the radiator bleeds, and is the header tank got some water in it (if applicable)? Can you hear any air noise in the rads themselves?
John
Is there any air at the radiator bleeds, and is the header tank got some water in it (if applicable)? Can you hear any air noise in the rads themselves?
John
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It's not a whine with mine, it's the sound of water circulating/gushing around. The header tank is working fine. I had a new rad and valves installed recently and drained the system down. I did have air in the rads which I bled over the course of a few days and they're mostly fine now. I still get the occasional trickling sound in one of them but once the heatings off I bleed it and get a little air out. Am hoping this will stop soon.
I'm sure the pump was making this noise before we drained the system, but it's definitely no better now. Air would be my thought as well. Have I bled the pump correctly? Just open the big screw on the front until water starts to trickle out?
Is there anywhere else I should be bleeding other than rads and pump?
I'm sure the pump was making this noise before we drained the system, but it's definitely no better now. Air would be my thought as well. Have I bled the pump correctly? Just open the big screw on the front until water starts to trickle out?
Is there anywhere else I should be bleeding other than rads and pump?
G
gaswizzard
Remove the head and check for any sediment between impellor blades , MANY have been changed when a clean would of sorted it.
I guess some sediment could have got stuck in the pump when the system was drained. When you say remove the head, can you give me some more guidance please. Would I need to shut off the valves either side?
Alternatively, is there any chance of this sediment making its own way out over time? The way things have gone with this system I'm reluctant to touch anything in case it makes it worse!
Alternatively, is there any chance of this sediment making its own way out over time? The way things have gone with this system I'm reluctant to touch anything in case it makes it worse!
By all means remove the pump head for a clean- there should be isolator valves on either side of it.
This is where the fun starts though - if your isolators are gate type (with the red turn wheel usually) they should shut the water off (as they don't have a rubber washer this can't be always relied upon).
If the isolators have the screwdriver turn ball type, then they are almost guaranteed to leak afterwards, unfortunately
John
This is where the fun starts though - if your isolators are gate type (with the red turn wheel usually) they should shut the water off (as they don't have a rubber washer this can't be always relied upon).
If the isolators have the screwdriver turn ball type, then they are almost guaranteed to leak afterwards, unfortunately
John
D
DeltaT2
Have you removed the head & 'cleaned the can'?? There's a few Youtube videos showing you how to do this. Grundfos are not too happy about it, cause of their sales dropping.............
My isolater valves either side of the pump have a square head on them (like a radiator bleed valve only bigger) so I can imagine if I undo these then they will leak afterwards?
I'm guessing if they begin to leak afterwards then the only option would be another full drain down and fit new isolator valves?
I'm guessing if they begin to leak afterwards then the only option would be another full drain down and fit new isolator valves?
Going back to the theory of it being air in the system, from reading some other posts it seems there will be some bleed points on the system from within the loft. I've only ever bled air from radiators and ths screw on the pump itself. What sort of a valve am I looking for in the loft? And are these also likely to be seized?!
As an update, the water bubbling/whooshing noise is present from the second the pump turns on, but as the water heats up the whooshing noise gets louder and faster. Once up to temp, the noise repeats the following cycle - it seems to 'spool up' then releases really quickly for a while (similar noise to a fully open cold tap) then gradually quietens down then does it's quick 'turbo' style whoosh again for a while. Is this linked to what the boiler is doing?
For the time being the system's working ok, I'm just not used to these old systems so don't know if these noises are normal or not. You can hear it even with the airing cupboard door closed. The pump is on speed 2. On speed 3 the vibrations/hum it produced sounded like a plane was landing on my roof.
The system was drained down 2 weeks ago so could it be oxygen in the new water working it's way out? I'm still getting a tiny bit of air out of the magnaclean and one radiator.
Could air be being produced in the pump? Is that possible?
For the time being the system's working ok, I'm just not used to these old systems so don't know if these noises are normal or not. You can hear it even with the airing cupboard door closed. The pump is on speed 2. On speed 3 the vibrations/hum it produced sounded like a plane was landing on my roof.
The system was drained down 2 weeks ago so could it be oxygen in the new water working it's way out? I'm still getting a tiny bit of air out of the magnaclean and one radiator.
Could air be being produced in the pump? Is that possible?
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