Central heating Pump issue

[Bill goodwin]

Hi all. Posted last week issues with radiators. Upstairs hot and downstairs generally cool though now and again one gets warm. Been reading some forums which all state that the heating pump should be at most warm to the touch. Mine is red hot absolutely burning hot so much you cannot touch it. So appears something wrong which am hoping you will all agree. Anyway. Ordered new pump as process of elimination needs to be adopted. Once fitted I was going to lock all rads down and bleed the water through what I think is the last one in the system. This one is downstairs and is the biggest and also the coldest. Your thoughts please. Am I going about this the right way. Am hoping if there is an airlock the new pump will shift it. Or of my old pump is done for them the new one should make a difference.

 

[Mottie]

My pump is working fine but gets too hot to touch. Has been like that for years with no problems.

 

[Bill goodwin]

Hmm. Can’t remember mine being like that. Anyway took the plunge so see what happens. Thanks.

 

[Mottie]

I just thought mine was normal. I mean, it’s the first place the heated water from the boiler goes through, before any rads even, so it’s never going to be just 'warm' and will be hotter than any radiator.

 

[Bill goodwin]

That sounds reasonable. The pump I have has been in for over 10 years so it’s process of elimination mow.

 

[oph]

Hi all. Posted last week issues with radiators. Upstairs hot and downstairs generally cool though now and again one gets warm. Been reading some forums which all state that the heating pump should be at most warm to the touch. Mine is red hot absolutely burning hot so much you cannot touch it. So appears something wrong which am hoping you will all agree. Anyway. Ordered new pump as process of elimination needs to be adopted. Once fitted I was going to lock all rads down and bleed the water through what I think is the last one in the system. This one is downstairs and is the biggest and also the coldest. Your thoughts please. Am I going about this the right way. Am hoping if there is an airlock the new pump will shift it. Or of my old pump is done for them the new one should make a difference.

System on.

Shut your rads upstairs off, it should push the energy downstairs.

 

[Bill goodwin]

Thanks for posting. I have turned the rads down as much as I can as still want heat upstairs. Has made a little bit of difference but downstairs still only Luke warm. Am hoping a new pump will re energise the system. Once fitted going to turn all rads off except one to push any air through. Think that should work? Out of interest if o do this would it be better to leave one open upstairs or downstairs.??

 

[oph]

Thanks for posting. I have turned the rads down as much as I can as still want heat upstairs. Has made a little bit of difference but downstairs still only Luke warm. Am hoping a new pump will re energise the system. Once fitted going to turn all rads off except one to push any air through. Think that should work? Out of interest if o do this would it be better to leave one open upstairs or downstairs.??

If your pump is old then it might well be failing. Yes, could well help

 

[Bill goodwin]

Will let you know. Thanks.

 

[Harry Bloomfield]

Am hoping if there is an airlock the new pump will shift it. Or of my old pump is done for them the new one should make a difference.

Pumps usually either work properly, or do not work at all - nowt much in between. Pumps are most often replaced because they fail completely or become excessively noisy. A pump will normally get hot due to the heat in the water they are pumping. They might get a little hotter if they are seized, but checking for seizure should be the first check and an easy one to make - remove the chromed shaft end screw and see if the shaft is rotating.

Usually as a pump starts and stops, a flow of water can be heard through the system.

If it is rotating, then I would be looking for a reason why the water isn't circulating, such as the system's pipework being choked up with debris or an airlock.

 

[Bill goodwin]

I agree. I think there is an airlock somewhere. Also my header tank overflow had a flow of water coming out. Not excessively just a steady stream. Read that this might also be a pump problem. Either way the existing pump has been in since 2007! So I thinks it’s due a change. At the very least it eliminates that as the problem if rads still not working. Failing that I think it will be time for an engineer to come and have a look.

 

[Madrab]

Pumps usually either work properly, or do not work at all - nowt much in between

Have to disagree, cheaper pumps can get lazy, over time they lose torque and find it harder to push against the system resistance. This can be down to cheap internal components, overheated windings burning out etc.

All pump can get worn, contaminated by dirt and debris, corrosion can build up that can cause increased friction, all of these reduces their performance and lifespan.

If a pump lasts =>10Yrs then TBH it's done really well and if it's looking tired then it deserves a pat on the back and a quiet retirement.

It may not be the cause of the issue but it's certainly a good place to start and allows that component to be removed from the fault finding process.

 

[Madrab]

Testing by shutting off the rads upstairs as suggested is just a good temporary test to see with half the system shut down do the other rads get hot. A balancing exercise is another good procedure to go through.

 

[Harry Bloomfield]

I agree. I think there is an airlock somewhere. Also my header tank overflow had a flow of water coming out. Not excessively just a steady stream. Read that this might also be a pump problem. Either way the existing pump has been in since 2007! So I thinks it’s due a change. At the very least it eliminates that as the problem if rads still not working. Failing that I think it will be time for an engineer to come and have a look.

Pumps can last for decades, unless you know and have proven it has failed, it is pointless swapping it on the odd chance.

Pumping over at least proves the pump is pumping, but in itself is a fault and a possible issue. It will be pumping hot water into the header tank, which could melt a plastic tank and at the very least the excess moisture from the steam, can cause damage loft woodwork. Pumping over can be caused by the pump running too fast, poor pipework layout, or possible pipework blockages. In your case, I would suspect the later.

 

[Harry Bloomfield]

If a pump lasts =>10Yrs then TBH it's done really well and if it's looking tired then it deserves a pat on the back and a quiet retirement.

Our first pump lasted 30 years. It had no issues when it was replaced at all, it was simply replaced because it was due and for a more efficient one, which likewise has run for the past 11 years with no issues at all.