Boiler not shutting off. I think it's because a Grundfos pump is stuck on since smart meter install.

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We had a smart meter installed on the 6th.

Since then, the boiler has been constantly ignited, despite all hot water and heating switched off. I think the culprit is a Grundfos pump.

I am absolutely clueless on plumping, but need to get this fixed as our boiler is a 50kw unit and gas is expensive right now.

How can I best fix this?
 
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1. Smart meter installation very unlikely to be anything to do with the problem.
2. The pump doesn't "drive" the boiler, the boiler drives the pump.
3. Much more likely to be a controls issue. I would look at (in order):
3a. Motorised valve(s).
3b. Programmer.
3c. Room and / or hot water cylinder thermostat.
3d. Boiler itself.
4. What system do you have:
4a. Boiler make and model?
4b. Central heating set up. Motorised valve with one inlet one outlet? Motorised valve one inlet two outlets? Room thermostat? Radiators / Underfloor? Sealed system (no small tank in loft)? Open vented (small tank in loft)?
4c. Hot water set up. Motorised valve with one inlet one outlet? Motorised valve one inlet two outlets? Cylinder thermostat? Ordinary (vented) hot water cylinder? Unvented cylinder? No cylinder?
4d. What programmer?
 
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1. Smart meter installation very unlikely to be anything to do with the problem.
2. The pump doesn't "drive" the boiler, the boiler drives the pump.
3. Much more likely to be a controls issue. I would look at (in order):
3a. Motorised valve(s).
3b. Programmer.
3c. Room and / or hot water cylinder thermostat.
3d. Boiler itself.
4. What system do you have:
4a. Boiler make and model?
4b. Central heating set up. Motorised valve with one inlet one outlet? Motorised valve one inlet two outlets? Room thermostat? Radiators / Underfloor? Sealed system (no small tank in loft)? Open vented (small tank in loft)?
4c. Hot water set up. Motorised valve with one inlet one outlet? Motorised valve one inlet two outlets? Cylinder thermostat? Ordinary (vented) hot water cylinder? Unvented cylinder? No cylinder?
4d. What programmer?



I did think it was odd the smart meter would have this effect, but it only seemed to happen after they came.

I have recently moved into this property, so I do not know the ins and outs of the system. I am also a total novice, so I don't know all your answers. I have contacted the person that installed the system but he is not getting back to me, and it's pretty urgent that I get this fixed because of the cost.

The system, as I understand it, is as follows. It is quite unique as it's a single pipe system throughout the house.

Single Pipe Central Heating system, powering radiators throughout the property. About 2/3 of the radiators have Honeywell Thermostatic valves, the others have no TRV installed so are either on or off.
We have a Worcster 8000 50kw boiler.
This feeds the radiators, and also a 250L Joules Unvented Indirect Hot Water Cylinder.
All controlled by a Honeywell EvoHome system.
All fed of the mains, no tank in the loft.

There IS a small white tank next to the water cylinder, that is called a Zilmet Expansion Vessel, but again, im not sure what that does.

"Motorised valve with one inlet one outlet? Motorised valve one inlet two outlets?" - I'm sorry, I don't know how to check this to answer.




I have been trying to troubleshoot. I can turn everything off via the EvoHome controller, and the boiler remains ignited. The hot water doesn't seem to be the culprit as I can turned this off, confirmed the hot water ran out, and then turned it back on to get hot water back.
The radiators without TRV's are warm right now, but they should be cold as I've turned the CH off entirely. If I turn one of the radiators with a TRV on, said radiator will heat up and the not TRV radiators will get hot, as expected in a single pipe system.
 

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It is quite unique as it's a single pipe system throughout the house.
No it isnt a single pipe system is something completely different, if definately happend at tha same time as the smart meter install, the only thing they can do wrong is reverse the polarity, this however would not cause the problem you are having, more likely they have cut the power to install the smart meter and a control has went toits up, when power restored
 
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No it isnt a single pipe system is something completely different

Thats what we were told by the previous owners. Single Pipe System in that each radiator throughout the house is fed of a single pipe. It might be a bit different with the hot water factored in?

I am trying to get the installation engineer out to do a proper handover, so I can clarify all of this.

Regardless, the boiler is currently stuck on and prior to last week it was working as expected. Can you offer any advice on troubleshooting?
 
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Turn the mains electric supply off to the system.

I have tried this. I have cycled the boiler and the honeywell/Hot Water/Pumps via the circuit breaker, but the boiler reignites when I turn it back on.
 
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Ok. Turn off when you don't want heating on ,and turn on when you do ,until you can get an engineer to visit.
You should have a switch other than the circuit breaker .
 
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I guarentee from your pic that you do not have a single pipe system

I'm not disagreeing, I honestly don't know for sure. I just know that the radiator system is powered by a single pipe that runs throughout the house. Each radiator does not have it's own return pipe. Whatever the system is, I know that it's quite unique and a regular engineer won't work on it.
 
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I'm not disagreeing, I honestly don't know for sure. I just know that the radiator system is powered by a single pipe that runs throughout the house. Each radiator does not have it's own return pipe. Whatever the system is, I know that it's quite unique and a regular engineer won't work on it.
Hardly unique, very common in larger houses these days, actually looks quite well installed to be honest, get the one pipe idea out of your head , you dont have that system, say where you are and there may be someone on here that can recommend someone that covers your area
 
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post a pic of the control panel of your worcester boiler with all controls set to off and the boiler still firing
 
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post a pic of the control panel of your worcester boiler with all controls set to off and the boiler still firing

I am in Tamworth, North Birmingham/Staffordshire.

This pic is showing the evohome controller and the boiler. You can see the flame icon showing the boiler is lit. I had to move the controller to take the pic, so it lost connection to some of the radiator valves, but it should show the CH is off and the HW is off in the pic.
 

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OK thanks for that, as suspected one of your zone valves is calling for heat, either a seized synchron motor , or a stuck micro-switch, as the heat is getting away from the boiler I suspect a seized botor, in your first pic you have two zone valves (silver boxes) these have a little manual lever on the side , turn heating and HW off and try and slide the manual lever across to the manual position, both should show resistance, if one doesnt show resistance that is your fault
 
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