Anyone here have a clue about underfloor heating?

[swee'pea99]

Pumps do run very hot as there’s no external cooling fan. The windings are usually rated at 140 C . If you put a large screwdrivers with the blade on the chrome button at the back of the pump body and your ear on the other end you should hear a faint whirring sound as mentioned by others. You could try giving the pump body a few gentle wacks.

Yes you could.
And I did.
And...

Mark another one up for the CC crew!

Thanks everyone. Saved me probably £150 to have someone else come round and 'it it wiv a nammer.

The thing I'm not clear about at this point is what state to leave these

in. Usually when I've finished bleeding a radiator, I screw the screw home. But on these, I've found that if I screw the middle one right down, the gauge immediately below - ie, the flow rate - instantly goes from 4ish to zero.

So, do I screw down one/either? Leave one/either open?

Any help, as ever, much appreciated.

 

[Tenkaykev]

Yes you could.
And I did.
And...

View attachment 670975

Mark another one up for the CC crew!

Thanks everyone. Saved me probably £150 to have someone else come round and 'it it wiv a nammer.

The thing I'm not clear about at this point is what state to leave these

View attachment 670977

in. Usually when I've finished bleeding a radiator, I screw the screw home. But on these, I've found that if I screw the middle one right down, the gauge immediately below - ie, the flow rate - instantly goes from 4ish to zero.

So, do I screw down one/either? Leave one/either open?

Any help, as ever, much appreciated.

If it was me, I'd put everything back exactly as it was pre problem. If It was all tickety boo before the problem then it might well have been a sticky pump.
Perhaps switch the pump to its highest speed for a few hours to give it a bit of a blast.

 

[swee'pea99]

If it was me, I'd put everything back exactly as it was pre problem. If It was all tickety boo before the problem then it might well have been a sticky pump.
Perhaps switch the pump to its highest speed for a few hours to give it a bit of a blast.

Thanks. I don't actually know how everything was before I started messing about with it, but I've left both valves a bit open for now and fingers crossed for the morning, which is when I should know whether it has actually come back from the grave...

Wish me luck...

 

[CXRAndy]

I would suggest you reduce the flow rates down to around 2-3 litre/min. The water then has a bit longer in the circuit to release it's heat energy.

 

[Tenkaykev]

Thanks. I don't actually know how everything was before I started messing about with it, but I've left both valves a bit open for now and fingers crossed for the morning, which is when I should know whether it has actually come back from the grave...

Wish me luck...

Always take photos ( pre mobile phone cameras I would make copious notes and drawings)

 

[CXRAndy]

Yes you could.
And I did.
And...

View attachment 670975

Mark another one up for the CC crew!

Thanks everyone. Saved me probably £150 to have someone else come round and 'it it wiv a nammer.

The thing I'm not clear about at this point is what state to leave these

View attachment 670977

in. Usually when I've finished bleeding a radiator, I screw the screw home. But on these, I've found that if I screw the middle one right down, the gauge immediately below - ie, the flow rate - instantly goes from 4ish to zero.

So, do I screw down one/either? Leave one/either open?

Any help, as ever, much appreciated.

Just realised what you are doing there. There should be no need to remove the flow indicator, you rotate the bottom section of the valve body( actually yours have a box key top in clear) and you should see the flow rate adjust. Be Gentle with the adjustment

 

[swee'pea99]

I would suggest you reduce the flow rates down to around 2-3 litre/min. The water then has a bit longer in the circuit to release it's heat energy.

Interesting....

Always take photos ( pre mobile phone cameras I would make copious notes and drawings)

Oh, I do. It's just that in this case it's a screw that looks pretty much the same whether it's three or four turns up or down.

Just realised what you are doing there. There should be no need to remove the flow indicator, you rotate the bottom section of the valve body( actually yours have a box key top in clear) and you should see the flow rate adjust. Be Gentle with the adjustment

That's very interesting. Are you saying that these things -

adjust the flow rate, and that by turning the wee perspex 'nuts' on the tops I can adjust the rate down to 2-3 litres/min?

Thanks.

 

[CXRAndy]

Interesting....

Oh, I do. It's just that in this case it's a screw that looks pretty much the same whether it's three or four turns up or down.

That's very interesting. Are you saying that these things -

View attachment 671038
adjust the flow rate, and that by turning the wee perspex 'nuts' on the tops I can adjust the rate down to 2-3 litres/min?

Thanks.

Yes, all the manifolds Ive ever had, I adjusted the flow to balance them with either turning the bottom of the indicator or top.

If there is a brand on the manifold-Google installation and setup guidance

 

[swee'pea99]

Yes, all the manifolds Ive ever had, I adjusted the flow to balance them with either turning the bottom of the indicator or top.

If there is a brand on the manifold-Google installation and setup guidance

Thanks, I'll have a go. I did look for a brand, but can't see anything helpful.

 

[swee'pea99]

First off, thanks everyone - we're back in business! Warm kitchen, happy missus, hooray for the CC posse!

I've tried running the pump at a higher setting for a few minutes (it seems to have just two: what I thought was high position - three - turns out to be off) and everything seems to be tickety boo. The flow rates are now set at a steady four, and that seems to be working fine. So, thanks again - really appreciate your help.

 

[irw]

The thing I'm not clear about at this point is what state to leave these

View attachment 670977

in. Usually when I've finished bleeding a radiator, I screw the screw home. But on these, I've found that if I screw the middle one right down, the gauge immediately below - ie, the flow rate - instantly goes from 4ish to zero.

So, do I screw down one/either? Leave one/either open?

Any help, as ever, much appreciated.

I'm a bit late to the party I think, but jsut for clarification, assumign you're talking about the bit with the bleed key on it, these should stay fully open. If you had a zoned system, the actuators would sit on top (where you have the bleed key) and open and close as per heat demand from different areas

 

[swee'pea99]

It died again.

And there was me thinking it was one thing sorted. Nope. Same symptoms - cold room, flow rate stuck on zero - but this time the couple of taps on the pump with a hammer haven't made any difference. It just sits there, humming gently to itself...

It's hot, and if I put a long screwdriver to it and my ear to t'other end I can hear it humming quite urgently...like it's trying to do something, but can't. If I switch between the three settings (and contrary to what I said above, setting three is not off) I can hear/feel the hum changing frequency - but the flow rate remains zero.

Last time, when someone suggested a few taps with a hammer, I applied same and almost immediately there was this strange brief rumbling sound, like a 40-a-day smoker clearing his pipes in the morning, and the flow indicators immediately went to 3ish, and I thought that was that. And so it was. But now the low rates are stuck on zero again, but when I tap it, the magic trick no longer works...

What baffles me is, if the pump is burned out, why isn't it totally dead/quiet, and if it isn't, why won't it pump? Could it be blocked? (We've never had the rads/system flushed in the 25 years we've been here, and when I took the radiator out in the bedroom upstairs, the black filth that came out was truly grim.)

Is this the kind of thing a halfwit like me might be able to fix, or is it time to Get A Man In? At a glance, it doesn't look that challenging. Drain down the system, remove pump, proceed depending on revelations sort of thing...

Any thoughts/advice/handy hints & tips much appreciated.

Brrr!

 

[figbat]

It could be seized - the motor is trying to turn it but it is physically jammed and unable to turn. If it was on the way before it might now be finished. Pumps usually have isolator valves either side to make removal straightforward - if so you can take it out and see if the impeller will turn.

 

[swee'pea99]

It could be seized - the motor is trying to turn it but it is physically jammed and unable to turn. If it was on the way before it might now be finished. Pumps usually have isolator valves either side to make removal straightforward - if so you can take it out and see if the impeller will turn.

Thanks. Interesting. Would that be the big blue and red taps in the right-hand corners of this pic:

...so if I turned those off I could investigate the pump without having to drain the whole system?

 

[CXRAndy]

Most pumps have a big chrome centre key, with a flat slot. If you remove this a bit of water will come out, but you can see the motor spindle. It should be spinning. If it's not, something is jammed in the motor or the motor itself has seized. Lock off valves either side of the motor for removal/replacement

Looking at the direction of the Motor, the chrome key is facing the cabinet side on the left, difficult to access. I would loosen the fittings and rotate the motor so you can remove keyto check motor rotation

See images https://www.google.com/search?q=cen...=_d4fEY7XfGLTE8gKl4474DQ_31:22.85714340209961