Central heating pump and boiler

[nut&bolts]

Right, this means then most likely Valve fault....
[automerge]1603478645[/automerge]
As not returning to hot water position

 

[John.g]

I know you stated that the you have always only had CH or HW which would point to a W system but it is just possible that you actually have a Y plan (however unlikely) with a mid position valve which either has been wrongly wired or is faulty. To rule out any confusion can you just read the valve details and post back please.

 

[nut&bolts]

This is the valve also below is the picture of pipework

[automerge]1603480889[/automerge]

Above the pipework is the cylinder

 

[SJB060685]

You could have a sticking valve yes but that wouldn't justify the boiler coming on, that would require a signal from elsewhere.
As above confirm the type of valve you have but I think its time you had an engineer out to check it all over with a multimeter

 

[John.g]

It is a mid position valve and can you get the details off another motorised valve?? to the right of it in the second picture please. Forget that the grey unit is the pump, apoligies.

 

[nut&bolts]

There are no more valves. The other thing is the pump

 

[SJB060685]

That is a mid position valve, meaning you can have heating and hot water on at the same time or independently, unless of course its been wired as a diverter.
This does need a multimeter now. Someone needs to check what feeds you have where.

 

[John.g]

But we are making progress, we have figured out after 50 posts or so that it is a mid position valve.

 

[nut&bolts]

Okay , I call another plumber tommorow and highlight that electrical connection needs to be checked. Hope they don't rush to change valves to start with...

 

[SJB060685]

Okay , I call another plumber tommorow and highlight that electrical connection needs to be checked. Hope they don't rush to change valves to start with...

Thats your best bet mate. As I said above boilers don't just ignite on their own, something somewhere is telling it to. This could be a number of things all the way back to the boiler.

 

[Brambles]

From an earlier post you indicated that sludge in the system had been dislodged by Sentinel X400. Do you have a magnetic filter on the system return? If so is it removing magnetite?

Before you replace the boiler, run it independently by opening the heating valve, bridging the thermostat input and running the system on the boiler stat. If ok, then address the control system issues.

The best approach is a simple logical process to find the gremlin. Initially, eliminate the boiler as the culprit. From your postings, I doubt it is the boiler, but sludge in the system does not help with the diagnosis. Eliminate this as an issue first

 

[nut&bolts]

There is no magnetic filter. May be drain and refill it...
I see what the new plumber suggests. I will share the outcome in any case...

 

[nut&bolts]

I managed to get hold of two plumbers. Entire three port valve and programmer is charged. None of the plumber checked wiring plan completely. They were more interested in changing above parts.
Since three port valve is changed water and central heating now work together.

The main problem remains that boiler keeps randomly switching on for a minute to two and water becomes v hot. I have called another plumber who can only make next Monday..

Apart from wrong wiring, what are the other reasons for this. Any other suggestions?

 

[John.g]

In view of what you told them about random boiler firing then i presume (if they were capable of changing the programmer and valve) that they would have checked the wiring at the boiler and pump to see if separately wired or if the boiler PCB is switching the pump or whatever, maybe its something as simple as the pump being wired correctly and the boiler having a permanent supply to its switched live.

 

[nut&bolts]

In view of what you told them about random boiler firing then i presume (if they were capable of changing the programmer and valve) that they would have checked the wiring at the boiler and pump to see if separately wired or if the boiler PCB is switching the pump or whatever.
[/QUOT

In view of what you told them about random boiler firing then i presume (if they were capable of changing the programmer and valve) that they would have checked the wiring at the boiler and pump to see if separately wired or if the boiler PCB is switching the pump or whatever.

I was told that it doesn't have a PCB. It is with pilot light. Pump only gets on, when switched by programmer....
[automerge]1604153209[/automerge]
Pump can be switched on by programmer, even when the boiler power is switched off from plug on the wall

 

[John.g]

Then doesn't that imply that the boiler could be fed from anywhere (permanent live).

 

[nut&bolts]

Then doesn't that imply that the boiler could be fed from anywhere (permanent live).

This looks like a possible reason. How will they look at the wiring to exclude this ?

 

[SJB060685]

That implies that you have two incoming electrical supplies to the one system and the boiler is getting a feed from elsewhere. If this genuinely the case then you need someone with a good understanding of electricity to put right for you.

 

[nut&bolts]

Pehaps sould look for an electrician... So far plumbing engineers haven't checked with multimeter all the connections etc...

 

[SJB060685]

IF that is the case then it wouldn't be unheard of.
I learnt the hard way once when isolated what was thought to be the only incoming live to a system, I then touched what should have been dead only to get a shock.
I would have someone with suitable electrical qualifications to check it out and rectify.