water pump issue?

[finest1]

hi all,

the central heating water pump at my parents house seems faulty. it makes unusual noises like gurgling, groaning noises that we never heard before. further to this after just 2 mins in the pump gets very hot and the boiler switches off. the pump itself was originally installed in 1986!! as its the oldest component i am guessing it is that.

the system is a condensing boiler (Worcester bosch 18Ri) with an F&E tank in the loft. the pump itself is SMC comet 130-45 installed 1986 we have NO cylinder

i have done the following to diagnose the system:

Drained F&E tank and refill. all works ok, ball cock works fine. tank drains at a steady rate and also fills at a steady rate.

i have bled all the radiators in the house starting at the bottom. all fine

i have ran a magnet on the pipes in and out of the tank, and around the water pump, no pull on the magnet

i have attempted to diagnose the actual pump, but when i take off the cover, i cannot find any bleed screw

after the above, the pump makes a loud whirring noise when switched on, it runs hot, but does not groan and gurgle. the boiler switches off after 5 mins

i am wondering, or seeking advice what else i can do to get the pump working and ultimately the CH back up working. is it a faulty pump?

previous to this the CH has been running fine. we estimate we stopped using it in may, and last week we put it on to test if the heating was working fine

i will attach some photos.

please note i am not a plumber or CH engineer, i am a DIYer with a splattering of knowledge and experience

many thanks in advance

 

[ShaunCorbs]

Pumps gone / cap

You can try testing the cap and then if bad changing the capacitor first if you want

 

[finest1]

thanks for your quick reply shaun. how can i be sure its not an airlock issue? i don't mind changing the pump, its served us well! but it will be pointless having a new pump if i there are outstanding issues.

 

[ShaunCorbs]

Have you drained the system?

 

[finest1]

Have you drained the system?

hi shaun, yes, i drained the system to check for any cold feed blockages on the F&E tank. there was no issues. it drained and filled up at a steady rate

 

[ShaunCorbs]

Did you fully drain the system or until you heard the tank running ?

 

[finest1]

Hi Shaun, I was actually up in the loft. I watched the tank drain all the way , and watched fill back up, if that’s what you mean, thanks

 

[finest1]

hi all update:

i drained the tank in the loft and all the radiators today. i then went through the bleeding process once the water was reinstated. there was no issues with the tank re-filling and the ball valve closing the water. after the whole process. i attempted the central heating and same result. the boiler lasted 2 mins and shut off. the pump was not making excessive noise but it didn't "sound" right. whole process took me 2.5 hours.

any suggestions?

thanks

 

[ShaunCorbs]

Turn the hot water on only and the boiler temp to min and let it run

 

[finest1]

Turn the hot water on only and the boiler temp to min and let it run

hi Shaun just a reminder that this is a condensing boiler not a combi. the boiler is for the central heating only. however, do you still want me to try?

thanks

 

[ShaunCorbs]

Yes as the hot water circuit eg upto the cylinder is the shortest circuit normally any bleeder / venting points around the cylinder?

 

[finest1]

hi shaun, just to remind you i don't have a cylinder. you want me to still try?

 

[ShaunCorbs]

How do you have hot water then ?

 

[finest1]

we get domestic water via a " Main Multipoint BF ERP Gas(Natural)Water Heater" in the bathroom which supplies our hot water for bathroom and kitchen

 

[ShaunCorbs]

That’s fair enough so shut all the radiators but the closest one to the pump and then run the system

 

[finest1]

OK i'll give this a go tomorrow, and i will update you. thanks for your time

 

[finest1]

hi Shaun, i gave it a go. for a heartbeat i thought it was going to work! however it didn't. same as above, boiler shut off.

thanks

 

[ShaunCorbs]

Did you keep bleeding any air off the rad !

 

[finest1]

dear all, thanks for your advice. i'd like to give you an update:

i called in a CH engineer to help resolve the issue. to cut a long story very short, he did think there maybe 2 issues, airlock, or water pump. he decided to go down the water pump route and said lets see what happens. he changed the water pump and then bled the boiler. so i have no issues there. during the install he had to apply force to remove the pump, that's fine we knew that from the conversation above. so all was fine, everyone happy. however during the install he decided not to change the valves to the new ones. i asked why. he said 1) we would have to drain the system and could cause an airlock 2) the valves are fine, no need changing them if we don't have to. i was surprised by this, and told him so, but took his advice. all good. i went to check the install hours later, and saw the water pump and valves wet. it was almost like it was sweating, but we had to put a container under to catch the drip. i text him and sent a video. he said he will come next day and he did. however, this is the heart of the matter. he tried to tighten it and the weep was still there. he then says to me, "your valves are defective". i reminded him that he confirmed the valves were fine and they didn't need changing, so you cannot tell me that i have defective valves. they weren't defective for over 30 years. he then said there is nothing he can do, he will have to charge me to change them. his job was to change the water pump only, valves wasn't part of the job. i then replied and explained to him that when i booked a job with the office, i said my CH doesn't work, i think its the water pump. during the conversation i told them i have the pump and valves on site. I told him all this when he came to the house, and gave him the pump and valve to hand. he declared its a separate job, nothing he can do and left.

at this point, i think its worth me saying that when i booked the job, i asked the office if the engineer can call me before hand as i will be happy to drain the tank, if that helps save time. the office said that they will get him to ring. he didn't, i didn't hear anything, he phoned me to say he's outside my house. he was two hours early, which i wasn't complaining about.

i lodged an investigation with the firm which, as you can imagine, is slow. promises of "I'll call you back" but never do. the latest conversation is that they are willing to replace the valves but its chargeable.

so i am hoping to get some perspective on this. i feel that the company should replace the valves with no cost as the engineer had caused some damage to it, they don't think so. they're stance is that they were only there to change the water pump.

what do you think?

thanks

 

[ShaunCorbs]

The valves are fine did he clean the face up and put new rubber washers on

If he damaged the nuts you can replace these by just using the slots on the underside of them and removing them

Would call them back and say it’s leaking and you want there insurance number as it’s going to cause damage

 

[finest1]

The valves are fine did he clean the face up and put new rubber washers on

hi Shaun. yes he cleaned the threads and changed the rubber washer which came with the pump.

If he damaged the nuts you can replace these by just using the slots on the underside of them and removing them

can you direct me to where this is? i upload a photo

Would call them back and say it’s leaking and you want there insurance number as it’s going to cause damage

i have a video which i sent to him. can i upload it here?

thanks

 

[ShaunCorbs]

https://www.stevensonplumbing.co.uk/images/source/Plumbing/heating/pump_valve_nut.jpg

Do you see the open two slots you can remove by tilting the nut and sliding it through the face on these

Tbh shouldn’t be leaking providing both the pump faces and the body faces are clean

 

[John.g]

I've seen those slots Shaun on the very few that I've changed but a bit confused as to what exactly their purpose is?.

 

[ShaunCorbs]

I've seen those slots Shaun on the very few that I've changed but a bit confused as to what exactly their purpose is?.

So you can swap the nuts

 

[finest1]

here are the videos:

water pump valve leak 1

water pump valve leak 2

 

[ShaunCorbs]

16mins onward

 

[ShaunCorbs]

Is it leaking from the pump nut or where the valve screws into ?

 

[John.g]

Ah, very good, so you could split the nut(s) if seized and just buy a new pair of nuts and slide them back on, we learn something new every day.

 

[ShaunCorbs]

Ah, very good, so you could split the nut(s) if seized and just buy a new pair of nuts and slide them back on, we learn something new every day.

Yes or you deform them trying to undo them eg oval I’ve put a video up that I managed to find

 

[finest1]

Is it leaking from the pump nut or where the valve screws into ?

i will be visiting my parents home later, i will have a look, now i know what i'm looking out for

 

[finest1]

Yes or you deform them trying to undo them eg oval I’ve put a video up that I managed to find

that could have been what happened when the engineer was trying to release the water pump

 

[John.g]

Couldn't watch the video but some of the older type had slotted ball vale (with O ring seal) for isolation and these invariably leaked out of the seal when reopened.......new valve required, the better type have a gate valve that don't leak, if yours arn't leaking like this then you can just isolate the water at both and renew the nuts (+rubbers) if required.

 

[hometech]

Electrical motors fail because of the load, the load in this case is the force required to move the valve...
engineers are highly educated, very bright people. Obtaining your BEng or MEng makes you a 1% of the 1%. They solve problems, they create solutions.
CH "engineers" or people who have an NVQ (and paid a private company never to be wrong) are at best technicians, you so it's not fair to expect them to be at the same level as a a real engineer.
The most thy do is guess and if that guess is wrong, they guess again. Imagine this was medical..they would be struck-off. Lower your expectations when dealing with the technicians and always be prepared to question their logic...

 

[finest1]

Is it leaking from the pump nut or where the valve screws into ?

update: the source of the leak is here. i've attached some photos. i double and tripled checked the whole fitting in case there was multiple leaks. thanks

 

[John.g]

That's a valve change out job IMO, it should have been quite obvious to "all" (being diplomatic) that attempts had been made to address this, probably attempting to tighten it/them.

 

[ShaunCorbs]

Yep time for a change

 

[finest1]

hi all, first of all, thanks for helping me diagnose and solve this issue. i really appreciate your time and your experience.

in regards to the dispute, as the days go by, i really don't think I'm going to get anything out of them. they are clearly ignoring me and hoping i'll go away. the latest is the person dealing with the complaint is just regurgitating technical jargon that the plumber has said, in order to try baffle me. but as i keep responding to anything they tell me, they get annoyed with me and start getting slightly aggressive on the phone. the latest is, they said they will see if they can do a discount rate for me to change the valves. however, no one is getting back to me. i can't imagine that takes days to figure out.

i will be tracking down the MD or owner of the company and going to contact them. is there a body i can complain to?

 

[finest1]

thanks again for helping me diagnose and solve this issue. i really appreciate your time and your experience.

as we now know the valves need changing, my options are:
can i do it myself?
or get someone else in?
let it run as it is for the winter, and in spring/summer we can get it resolved. however, will this cause any further problems?( my parents want to know if there is any issues with this idea)

if we look at the positives:

the heating is working
the water pump was the issue and now changed
engineer did bleed the boiler, and "service" it
all radiators are heating up fine.
no noise coming from the pipes, pump or boiler. if it wasn't for the leak it would be case closed.

i will be looking on youtube to see video demonstrations (if available) on how to change the valves. however, i think i would need a walkthrough/guide of how to go about it, and any drawbacks i would need to know BEFORE attempting it. i would love to get your input on this as you already been helpful.

i did watch the video shauncorbs sent. i was interested in how the plumber changed the valves over without changing the olive. i thought any fittings with olives, best practice was to remove and put new one in. anyway, the time stamp is 11:50 and 14:20. however, it could be a totally different situation.

thanks

 

[ShaunCorbs]

Drain down and undo both nuts install the new valves and re fill there’s a video above how to do it

 

[finest1]

Thanks, when draining, i'm only draining the tank, not the radiators. is that right? or the WHOLE lot, radiators too?

 

[ShaunCorbs]

Whole lot / anything at the same level as the pump if it’s lower you won’t need to drain this

 

[finest1]

can i just raise one point. the engineer said he didn't want to change the valves as this would involve draining the system and potentially cause an airlock. i know we've discussed airlocks in this post already, and i'm not disputing this, as it could. however, is this something i need to be prepared for? or the likelihood is low.

 

[John.g]

You don't have to drain the rads (and probably better off not draining them IMO) but you will have to shut tightly the lock shield valves at either end or a lock shield + a TRV, if installed, the TRV doesn't have to be squeezed up, just turn it clockwise until it comes to its stop.

 

[finest1]

this is a very crude diagram of where the water pump is located in the house. the drain off is on the lower ground radiator. hope this helps

 

[ShaunCorbs]

Yep drain the whole lot

 

[finest1]

Yep drain the whole lot

thanks

 

[finest1]

hi all, thinking ahead to if i successfully change over the old valves to the new ones. is there a way i can slowly release the water when checking for leaks? for example when i did some work on my shower. i would turn off at the main. when testing, i only add one turn to allow some water to come through. if it leaks, it will be at low pressure and enough for me to just switch off. at mine i don't have a tank in the loft. in this case i do.

thanks

 

[John.g]

If the pump is on the ground floor open any radiator vent that is just above it, start filling the system, stop filling as soon as water comes from the vent and inspect the pump/valves for leaks. If the pump is located higher up then you have to fill to a higher level.