Boiler/heating issue

[BlueLoo]

That was done without my knowledge and I only got to know this post replacement.

The motorised valve issue I saw with my eyes, the valve was only able to go to 2 out of 3 positions irrespective of the call from the programmer. But it worked fine prior to installation of the pump so I am assuming that this was somehow caused by what work was carried out.

Which two positions?

 

[Rayniac]

From what I recall it was capable to move to heating and combined, but not to hot water only.

 

[Harry Bloomfield]

That was done without my knowledge and I only got to know this post replacement.

The motorised valve issue I saw with my eyes, the valve was only able to go to 2 out of 3 positions irrespective of the call from the programmer. But it worked fine prior to installation of the pump so I am assuming that this was somehow caused by what work was carried out.

That 3=port actual valve, is an old one. They have replaced just the actuator part, the head.

Strange that what was just a noisy pump has accumulated lots more problems once they get to touch it and you still don't have a working system, despite all the parts replaced.

 

[BlueLoo]

From what I recall it was capable to move to heating and combined, but not to hot water only.

Can it do it now?

Have you checked?

That's an old valve.....

 

[Rayniac]

Yep, the valve works fine now, capable to switch to all three positions.

 

[BlueLoo]

Yep, the valve works fine now, capable to switch to all three positions.

Ok. Water should flow one way or another i suppose.

I found this to work.
Find the worst rad for airlocking. Usually the highest or furthest my away from the boiler.

Using a bowl, drain off a significant amount of water through the bleed nipple.
Do same for other rads where you suspect the airlock might be.
Top up inhibitor if you've drained a lot of water out.

I'm sure the pros may have a better way (reverse flow into the bleed nipple).

 

[Harry Bloomfield]

Yep, the valve works fine now, capable to switch to all three positions.

The actuator is moving, but you certain the valve is also moving, moving to the correct positions and actually allowing the passage of water at those positions? It all sounds so very suspicious.

 

[Rayniac]

OK, you are right that I am not certain if the actual valve is moving properly (as per what the actuator shows). But please correct me if I am wrong here - when I looked at the diagrams and how the actuator and valve moves, it seems to me that it is not possible for the flow to be blocked. It appears that I can get incorrect flow (i.e. only heating or both heating and hot water instead of hot water for example) but not a block that would prevent the water to be pumped from the radiator.

 

[BlueLoo]

Correct

 

[Harry Bloomfield]

OK, you are right that I am not certain if the actual valve is moving properly (as per what the actuator shows). But please correct me if I am wrong here - when I looked at the diagrams and how the actuator and valve moves, it seems to me that it is not possible for the flow to be blocked. It appears that I can get incorrect flow (i.e. only heating or both heating and hot water instead of hot water for example) but not a block that would prevent the water to be pumped from the radiator.

Normally you are correct, but if the valve has somehow broken up inside..

 

[Rayniac]

OK, I can see how this may cause issues, not sure if I will be able to check this though as I have limited tools and knowledge... also this is something that the second engineer worked on, which means it is covered by the guarantee the company provides. I will check if I can do this easily though...

As I am running out of options, I have booked another engineer (from another company) to come and inspect/diagnose the issue if they can. In the meantime I need to get back to the original specialists as well... I appreciate the suggestion of @BlueLoo but radiators were bled quite a few times (although not severely). As a matter of fact we did bleed 2 of them (upstairs) a lot since there was a lot of air in them - this was done prior to the works carried out as we hoped this was causing the issues with the old pump to start from. In any case I can try to bleed them again, it doesn't hurt.

 

[oldbutnotdead]

Yeah, don't think that type of valve has an off position. Still may be worth having the lid off and making sure the valve body is actually moving with the actuator. Also might be worth removing the actuator and manually operating the valve to its various positions.
Bottom line, water is not circulating through the system.
Possibilities;

1. Blockage caused by carp dragged into system when it was drained. Possible but lowish odds imho due to good condition of f & e tank.
2. Manual valve closed somewhere- again possible given the competence of the 'engineers'
3. System airlocked- possible looking at the collection of elbows near the pump
4. New pump faulty
5. New pump valve(s) faulty

OP, what does that red gate valve do? I don't think it's in the primary circuit but it's hard to tell- can you report back.
Is there another draincock anywhere near the boiler? If yes then open it full and leave it run for 10 minutes or so (yes you'll need to chuck some inhibitors in after that but again you need a working heating system first). (If there is a large airlock that might pull it through. If fully open you should get at least a gallon a minute through it).
We're then onto verifying the new pump valves and pump. Pretty lights on pump- good, and you say you can hear it whirring (good) but no sound of circulating water (bad). You'll need a couple of big wrenches for this step.And a washing-up bowl under the pump. Close both pump valves. Loosen one of the big nuts holding valve onto pump, doesn't matter which one tho it might be handy for later if you pick the one on the exit side of the pump. You should get a bit of water dribbling out but not much. If you get a flood that keeps going then retighten the big nut, fire the pump up, see what happens.
Assuming you got a dribble then it stopped, open one of the pump valves, leave it open for a minute or so. You should get a lot of water coming out. Close that valve, open the other one, you should get a lot of water coming out.
I know there's a lot of words there. First thing is look for random valves tampered with by bodgers. If you aren't sure what they do, post a pic showing the valve and as much of the pipework as possible. Or sketch what goes where.
Second is look for airlocks.
Do one stage fully before going onto the next (or you'll end up in a mess).

 

[terryplumb]

Either your boiler is air locked ,or the pump is starved of water. Have you got a fairly strong magnet ? If so ,run it around the TEE on the pipework , immediately to the left of the pump.

 

[Harry Bloomfield]

As a matter of fact we did bleed 2 of them (upstairs) a lot since there was a lot of air in them - this was done prior to the works carried out as we hoped this was causing the issues with the old pump to start from. In any case I can try to bleed them again, it doesn't hurt.

I'm not usually caught out, but I was caught out a few weeks ago doing the simple job of adding some inhibitor. I drained the level down in my open vented system, by just two mop bucket fulls. Added the inhibitor then refilled, bled and turned it back on. Boiler then went into lock out several times obviously due to an air lock. Funny part was I have never had a problem with air locks in the system in 40+ years, despite it being drained down a few times and partially drained a few times. My guess was that it must have been the level it was drained to which caused the air lock in this instance.

I cleared it eventually by opening 3-port valve, boiler off and pump running and lots of bleeding.

 

[Rayniac]

I cleared it eventually by opening 3-port valve, boiler off and pump running and lots of bleeding.

Do you mean radiator bleeding or should I be looking at another bleed valve/stopcock?