Water pump stopped in central heating

As my boiler was installed in 1999, this 'rumour' of the newer USP2 pumps damaging PCB on boilers doesn't rest easy with me.

It's all the more reason to get a pump that matches the power spec and operating mechanism as the original that was installed with the boiler back in 1999; hence the cheaper one being my preferred choice.

Really useful what I've learned in one day about water pumps!
 
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In looking at the valves I intend to buy (link in earlier posting):

20210802_061000.jpg


I notice they include a washer but only for the larger 1.5" end. This makes me wonder about two things.

1) The pump comes with two washers for each of its (large) 1.5 inch ends. Won't that give me a total of 4 x 1.5" washers? How many do I need to do the job?

2) Their appears to be no 22 mm washers for the smaller (pipe) end of the valves included with the valves. Is this a problem, do I need to purchase additional washers?
 
A little bit of lateral thinking goes a long way

If I ever saw a fitting that had green or black deposit like seen in the picture, I CERTAINLY would not go poking at it

As my boiler was installed in 1999, this 'rumour' of the newer USP2 pumps damaging PCB on boilers doesn't rest easy with me.

Millions of UPS pumps fitted in boilers. Almost every boiler is spec’d with a UPS pump
Pump in the picture was a dumb pump where power went directly to the coils via the three position speed selector. UPS pump is full of electronics, may even be more powerful than your 15/50 ( which is the number, at least, I would be interested in if pump was to be replaced)

Early Grundfos smart pumps caused electronic failures but that was corrected with special lead, present offering nil issues.

BTW, valves on your pump, unless these are well made, majority are not, I have found even the new ones to weep let alone when in service- replace with pump and have a spare to hand also:whistle::whistle:
 
Their appears to be no 22 mm washers for the smaller (pipe) end of the valves included with the valves. Is this a problem, do I need to purchase additional washers?

Is this a serious question?
 
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Do yourself a favour and get a pro in before you seriously f it up because whilst the pros will gladly assist with non flushing bogs and tap washers nobody really wants to see a train wreck coming...
 
UPS pump is full of electronics

Do you mean the UPS2?


2) Their appears to be no 22 mm washers for the smaller (pipe) end of the valves included with the valves. Is this a problem, do I need to purchase additional washers?
Is this a serious question?

Yes, this is a serious question, do you know the answer? If you know the answer to my question 1) as well, I'd be grateful.


Do yourself a favour and get a pro in before you seriously f it up

This isn't the first time I've being told this on the forum. Please, I really appreciate the help/assistance/advice AND my very specific questions being answered - it's how I learn. I'd rather this didn't turn into a "You're questions are so stupid that your almost definitely going to make a mess of this" debate.

Remember this is a DIY forum.

I haven't messed up one thing/project yet with the fantastic advice/answers that great people on this forum have given me.

Every word typed to help me out is fully appreciated.
 
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Make sure you have plenty of sacrificial towels to mop up.
1st victim will be the wiring centre below and next to the pump.
Protect that with bin liner and don't let water get into it.
The 22mm ends of the pump valves use olives and not washers.
I would be removing old olives and nuts, cleaning up pipe ends and using new ones from replacement valves, along with some paste if pipe ends are indented.
Use rubber washers on pump unions instead of the fibre ones.
Future use of those ballofix type pump valves will likely produce further weeping.

If my advice poses further questions for you, I would really suggest getting a plumber in or going on a course.
 
If my advice poses further questions for you, I would really suggest getting a plumber in or going on a course.

Or get a heating engineer in to do the pump change and you watch and learn for future attempt. Without being negative, there are some aspects to this task which are evident and need no advice.

One big problem I expect you might have for a start is, have you tried loosening the pump nuts? Have you considered what will happen when you remove the pump valve/s. If you empty the system, will it fill ok or will the air locks then open another can of worms. What about uncontrolled flow of water when you remove the pump valve, especially from the bottom connection.

What is a walk in the park for a heating engineer who will be able to do this task eyes closed and one hand tied behind his back, there are several hurdles here that will be stumbling blocks.

All said, crack on, faint heart never won a fair lady
 
The reason for bunging the tank, is so that you don't have to drain the system, thus avoiding airlock problems when you refill.
 
That's useful having the olives explained, I've just watched a YouTube video on the matter. If new valves DEFINITELY come with olives (see my earlier post for link to valves I intend to buy) then I would like, as you suggested, dilalio, to attach new ones. Removing the old olives does seem difficult, even with using both arms!

Would this tool be a good idea, as I have a rather small space to work and that olive on the bottom pipe is going to be difficult to 'knock up'?

https://www.amazon.co.uk/tesa-UK-Wa...rds=ptfe+tape&qid=1627888646&s=kitchen&sr=1-4


With regards to preventing future weeping; the chap in the YouTube video recommended using PTF tape to ensure a tight seal: would this be better than using paste?

https://www.amazon.co.uk/tesa-UK-Wa...rds=ptfe+tape&qid=1627888646&s=kitchen&sr=1-4

If not, can you recommend a paste and how it would be applied?


One big problem I expect you might have for a start is, have you tried loosening the pump nuts?

No, I haven't tried that but I have a set of water pump pliers (https://www.amazon.co.uk/gp/product/B0779CC4WJ/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1). These helped me to loosen a nut on my toilet which seemed IMPOSSIBLE to loosen.


Have you considered what will happen when you remove the pump valve/s.

Yes, the system has been drained, though I will have towels at the ready.


If you empty the system, will it fill ok or will the air locks then open another can of worms.

I think it's important to remember to OPEN the new valves FIRST before filling the system. Any airlocks that do occur can be dealt with by the air release pipe at the back of my cupboard (see in first pic of first post), bleeding radiators and venting new pump. This is to be done BEFORE switching on system?


What about uncontrolled flow of water when you remove the pump valve, especially from the bottom connection.

This system has been drained so I can't see this happening.

However, once new pump and valves are fitted it could happen and this would clearly be the nightmare scenario which would require me to do three things at once:

1) Close both of the new valves.
2) Run up loft ladders, breaking my leg in the process and stop water supply to small water tank.
3) Run downstairs, outside and open tap to drain system.

After that is all done, then reasses.


What is a walk in the park for a heating engineer who will be able to do this task eyes closed and one hand tied behind his back, there are several hurdles here that will be stumbling blocks.

I'm under no illusions as to the challenges I'm about to face. I'd like to think that my questions are symbolic of my humbleness and respect of the skills, experience and expertise you guys have.

Oldbutnotdead, I felt I had to drain the system yesterday as, on turning the old valves, they wouldn't stop weeping. As for the crud in the loft tank; I was lucky that I cleaned the tank a year or two ago: there is a thread on the matter on the forum. Worth pointing out that the water that drained outside the house looked remarkably clear.
 
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No, I haven't tried that but I have a set of water pump pliers (https://www.amazon.co.uk/gp/product/B0779CC4WJ/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1). These helped me to loosen a nut on my toilet which seemed IMPOSSIBLE to loosen.

Let me give you a little tip, don't even bother trying to undo the big pump nuts, there is no point.

Instead make up the new pump with the two new pump valves using the rubber washers that come with the pump instead of the fibre washers that come with the valves.

Next take out the whole existing pump and valves in one piece by undoing the smaller nuts (with olives), put in the whole pre-assembled pump & valves replacing the nuts and olives if you need too (personally I would not) with a couple of turns of ptfe or smear of jointing paste covering the olive.

The above is of course assuming you have drained as you said you intend.

EDIT: Make sure you get it in the right way around, there is an arrow on the side of the pump, note the direction of the old one before removing it.
 
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Thanks, kudos1uk.

I was just in the process of making up a step-by-step procedure and got a bit stuck with the order on how to attach the new stuff.

Two questions:

1) Removing and attaching the whole unit as one will require moving the pipes by a good few cm, perhaps 4 or 5? Is there usually enough play with the pipes to manipulate them that much?

2) Why wouldn't you replace the olives? Is it because they are so difficult to remove that the gain is likely not worth the effort?

I have ordered (all from amazon) pump, 2 valves, 2 rubber washers, olive removal tool and PTFE tape, total cost £88. I should have it all by end of week.
 

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