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Hi everyone

My father in law is having new Honeywell S Plan Controls fitted as the current ones are old/not working correctly.

I'm starting fresh with it all from the wiring centre. The only thing which has thrown me is the boiler has an interal pump as well as the standard pump upstairs in the cylinder cupboard. Do these both both need to be connected as with the S Plan diagram or do they both get wired directly into the boiler?

At the moment they are both wired into the boiler direct. I'm not sure if this is right or not as he thinks it's never been connected right since day one. The boiler is a Main HE 18.

According to an S Plan wiring diagram the non boiler pump connects in with the orange from the zone valves.

Thanks in advance.
 
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Hi everyone

My father in law is having new Honeywell S Plan Controls fitted as the current ones are old/not working correctly.

I'm starting fresh with it all from the wiring centre. The only thing which has thrown me is the boiler has an interal pump as well as the standard pump upstairs in the cylinder cupboard. Do these both both need to be connected as with the S Plan diagram or do they both get wired directly into the boiler?

At the moment they are both wired into the boiler direct. I'm not sure if this is right or not as he thinks it's never been connected right since day one. The boiler is a Main HE 18.

According to an S Plan wiring diagram the non boiler pump connects in with the orange from the zone valves.

Thanks in advance.

please get someone who knows what they are doing because if you read the manual for the boiler you will see its a system boiler and does not require a heating pump other than the one fitted to/on the boiler
 
What's the pump in the cylinder cupboard for? Is it a circulating pump?
 
Thanks for the quick replies. I'm not a plumber but it's a pump that sits on the pipe just before the zone valves.

Corbs I have seen the manual but only looked at the connections. Does it state that it doesn't need the heating pump?
 
With a modern boiler the circulating pump must be connected to the pump overrun terminal of the boiler, not the orange of the valves.
What is the pump in the airing cupboard doing? is it a circulating pump, HW secondary circulating pump, U/Floor heating pump, redundant?
 
Thanks for the quick replies. I'm not a plumber but it's a pump that sits on the pipe just before the zone valves.

Corbs I have seen the manual but only looked at the connections. Does it state that it doesn't need the heating pump?

you would only need to have second the pump if you have trvs on every rad in the house/flat and no heat leak etc to save the boiler boiling (to dissipate the heat from the system)

S Plan Help {filename} | ElectriciansForums.net
 
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Thanks for the quick replies. I'm not a plumber but it's a pump that sits on the pipe just before the zone valves.

Corbs I have seen the manual but only looked at the connections. Does it state that it doesn't need the heating pump?

Was it installed at the same time as the boiler, or was it left there from a previous system?

It sounds like it is redundant and should be removed
 
The pump in the cylinder cupboard is a circulating pump. It was replaced by a plumber about two weeks ago. The pump is red hot to touch.

Corbs it is a Main HE and not a HE A. Not sure if there is much difference?
 
The pump in the cylinder cupboard is a circulating pump. It was replaced by a plumber about two weeks ago. The pump is red hot to touch.

Corbs it is a Main HE and not a HE A. Not sure if there is much difference?

a rated efficiency i believe but doest matter if it have a pump inbuilt should have one on the system unless full trv's
 
The pump in the cylinder cupboard is a circulating pump. It was replaced by a plumber about two weeks ago. The pump is red hot to touch.

Corbs it is a Main HE and not a HE A. Not sure if there is much difference?

and the pipes hot as well ?
 
Manufacturers instructions. Two flex cables from PCB one says mains other says pump.

i would double check you have a system boiler and not a heat only boiler look under the boiler and look up you should see a pump if you dont its a he boiler and wire it up like a normal s plan with the pump by the cylinder (which i think you have) , if you do you don't need the second pump and wire it up like main say
 
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Just had a look and it says this in the manual: -

4. The boiler incorporates a circulating pump and expansion vessel. It is suitable for use only on fully pumped sealed systems.
 

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