Water pump stopped in central heating
- Thread starter MoonMan2
- Start date
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Worked on this today and just finished.
Took two-and-a-half hours.
Had to remove electrics from old pump:
This wasn't too difficult, just push the clip and pull out the wires.
It was easy to loosen the top nut but the bottom one took considerable force using the largest long armed wrench I had. Once the nuts were off, by manipulating the pipe a couple of centimetres, the whole thing came off as a single unit.
New pump with new valves fitted. The new olives and nuts, as advised, were not used.
It was difficult and fidgety to attach some PTFE tape around olives.
The new unit fixed very easily and tightening the nuts was no trouble. Though, I ended up with the valve screws not pointing front.
The electrics, easy enough.
The clips made it simple.
Job done!
I take it this can't go in a normal bin and needs to be taken to recycling/disposal ground?
After flooding the system and bleeding it; it was time to test.
No leaks, no drips - thank God!
Heated up the water perfectly.
The new pump appears to be more efficient than the last; I could put the new pump on setting I, and it worked well. At setting II, the entire system was louder, sound of water pumping through. At setting I, more a gentle action with the desired result of water heating.
I'll of course experiment with the settings.
Yes, I'm quite pleased with myself but the biggest thank-you has to go to you guys who trained me remotely on how to do this job.
You're ALL great!
Took two-and-a-half hours.
Had to remove electrics from old pump:
This wasn't too difficult, just push the clip and pull out the wires.
It was easy to loosen the top nut but the bottom one took considerable force using the largest long armed wrench I had. Once the nuts were off, by manipulating the pipe a couple of centimetres, the whole thing came off as a single unit.
New pump with new valves fitted. The new olives and nuts, as advised, were not used.
It was difficult and fidgety to attach some PTFE tape around olives.
The new unit fixed very easily and tightening the nuts was no trouble. Though, I ended up with the valve screws not pointing front.
The electrics, easy enough.
The clips made it simple.
Job done!
I take it this can't go in a normal bin and needs to be taken to recycling/disposal ground?
After flooding the system and bleeding it; it was time to test.
No leaks, no drips - thank God!
Heated up the water perfectly.
The new pump appears to be more efficient than the last; I could put the new pump on setting I, and it worked well. At setting II, the entire system was louder, sound of water pumping through. At setting I, more a gentle action with the desired result of water heating.
I'll of course experiment with the settings.
Yes, I'm quite pleased with myself but the biggest thank-you has to go to you guys who trained me remotely on how to do this job.
You're ALL great!
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Well done. 
Too late now for you, but I would have used gate pump valves because in my experience the quarter turn ones "always" leak !
I do not understand why you could not fit your valves facing forwards because when the nuts were loose they can be rotated as you desire.
I would expect to be able to rotate then even now on a gravity system by slightly loosening the two nuts without needing to drain the system.
I do not understand why you could not fit your valves facing forwards because when the nuts were loose they can be rotated as you desire.
I would expect to be able to rotate then even now on a gravity system by slightly loosening the two nuts without needing to drain the system.
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But aren't gate valves a tad longer than ball type, making direct replacement difficult?
Also for ordinary isolation, consensus seems to be that quarter-turn ball valves are better than gates, but apparently not for pump valves (I appreciate there's more to standard ball valves than pump iso valves)
That's why I stuck with the ball type.
I hear you; though the consensus of opinion on the thread was that because I will only be using the boiler for1 or 2 hours per week, it was sensible to go for the cheaper machine, as I am unlikely to wear-it-out at that rate of usage.
The gate pump valves are a little longer but it only takes a few minutes with a pipe slice to shorten the pipes, ideally just one of them. Providing the pipes allow that of course.
The problem with the pump ball valves is that they leak at the gland and virtually all do that if they need to be turned.
The ball type isolating valves are mostly very good quality and very reliable indeed.
Quite likely all the old pump needs is a new capacitor!
The problem with the pump ball valves is that they leak at the gland and virtually all do that if they need to be turned.
The ball type isolating valves are mostly very good quality and very reliable indeed.
Quite likely all the old pump needs is a new capacitor!
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Possibly, but with support from this forum the OP has done some "proper" plumbing and has the satisfaction of a working system.
Why p*** on his chips?
If I may question, why would I want to turn the valves? In the years I had the previous pump and valves, I never touched it.
Reducing the pipe length would have meant using a further new tool, a "pipe slice" as well as the issues in having to remove/(and attach new) olive on the reduced length of pipe. It would have complicated the already 'high-stake' task.
That all said; it's complimenting that in looking at my work, some are essentially telling me that I would have been competent enough to have taken it further. Earlier postings on this thread some were suggesting that I do not attempt the job at all and just to get a plumber in.
Reducing the pipe length would have meant using a further new tool, a "pipe slice" as well as the issues in having to remove/(and attach new) olive on the reduced length of pipe. It would have complicated the already 'high-stake' task.
That all said; it's complimenting that in looking at my work, some are essentially telling me that I would have been competent enough to have taken it further. Earlier postings on this thread some were suggesting that I do not attempt the job at all and just to get a plumber in.
so you have just had to drain the system to change your pump and change the leaking valves ....There is your answer , it doesnt get any simpler.
And no the valves are not always a different size but in any event , Why would you have to buy a pipe slice have you never heard of a junior hacksaw available for a quid in the cheap tool bins in supermarkets
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Exactly. The OP did mention that there didn’t seem to be enough room to get longer gate valves in there between the flooring and the 90° elbow above. The OP has done a good enough diy job and as he says, it’s not like he's going to be changing the pump every week. If he has to change the pump again, he should get at least get one use out of those valves and if not, so what, he can drain down again.
@MoonMan2 - As you drained the system, did you put corrosion inhibitor back in?
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