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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
 
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)

Straight-trv-image-for-box.jpg
 
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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
 
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.
 
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.

(no f and e tank in the loft then) wire it up as pg 14/ what ever it is in your man book then depending on what valve you have 2 or 3 port
 
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My Dads a Plumber and he's convinced there isn't one from the manufacturers instructions. I'm gonna have a visual check on it tomorrow and report back! Thanks.
 
Circulating pump in cylinder cupboard went so that was replaced by a Plumber about two weeks ago. When pump was changed water ****ed everywhere and got onto one of zone valve which blew. He then got a second hand one from shed and fitted it. Now when he turns room stat down the heating stays on. Second hand zone valve must be faulty as well. The whole wiring centre box is broke and needs replacing. He wants to uofate update st699 programmer to a digital one. Got a complete kit for £140.
 
Why not also get an experienced electrician to do the job?
Most of is will charge more to pick up the pieces of a DIY job than to do it from the outset.
Plus there is the small matter of electricity being somewhat deadly if you make the simplest of mistakes,
 
I appreciate your help davesparks but this forum is about helping each other and exchanging ideas. I don't know your electrical background and you don't know mine. Straight away like most people on here you assume I am a DIY'er for asking a question. I used to come on here a lot but it's these remarks what annoy me.
 
Circulating pump in cylinder cupboard went so that was replaced by a Plumber about two weeks ago. When pump was changed water ****ed everywhere and got onto one of zone valve which blew. He then got a second hand one from shed and fitted it. Now when he turns room stat down the heating stays on. Second hand zone valve must be faulty as well. The whole wiring centre box is broke and needs replacing. He wants to uofate update st699 programmer to a digital one. Got a complete kit for £140.

My Dads a Plumber and he's convinced there isn't one from the manufacturers instructions. I'm gonna have a visual check on it tomorrow and report back! Thanks.

thought you said your dad was a plumber?
 
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Yea. I've managed to find the correct documentation now. There isn't a pump inside the boiler just a standalone pump in the cylinder cupboard. The boiler manual says to wire the pump direct to the boiler pcb terminals instead of the wiring centre.
 
Yea. I've managed to find the correct documentation now. There isn't a pump inside the boiler just a standalone pump in the cylinder cupboard. The boiler manual says to wire the pump direct to the boiler pcb terminals instead of the wiring centre.

yes that's right because of pump overrun to dissipate heat
 
Yea. I've managed to find the correct documentation now. There isn't a pump inside the boiler just a standalone pump in the cylinder cupboard. The boiler manual says to wire the pump direct to the boiler pcb terminals instead of the wiring centre.

Cool, easy then standard S-plan with pump overrun. What S-plan pack have you got out of interest?

edit: just seen op where it says honeywell.
 

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The current set up he's got a Honeywell ST699 2 channel programmer, Danfoss Room Stat, 1 x Honeywell zone valve and 1 x ACL zone valve. He wants to buy a complete new control pack which we can get a Honeywell one complete with digital programmer and wiring centre for £140. Next time I'm round I'll post a photo with the state it looks at the moment. It's bodge after bodge over the years. The wiring centre has broke with no cover and with having young grand kids he wants it all making safe.
 
I appreciate your help davesparks but this forum is about helping each other and exchanging ideas. I don't know your electrical background and you don't know mine. Straight away like most people on here you assume I am a DIY'er for asking a question. I used to come on here a lot but it's these remarks what annoy me.
Your right there do seem to be a few annoying remarks made on this site which is why I stopped visiting for a while. Thought I'd come back to see if things are better. Seems not!
 
the only problem i don't like with danfoss is there time clocks just dont like the look and program of them so i just install drayton lifestyles much better and easy to change times even for the old people around :)

I don't mind them TBH, Honeywell is my 1st choice and Danfoss is my second. Whats put me off with the drayton lifestyle programmers is ive Been out to a few faults where Drayton has been installed and both times it's been the programmer sticking on. Saying that though I know British gas use Drayton lifestyle programmers marked up with their own logo so can't be that much of a common fault other wise they wouldn't use them.
 
Quick update for this problem that started a few weeks ago. When heating channel off and and hot water selected the radiators get hot. We put this down to a faulty zone valve on the CH. Fitted two brand new zone valves this morning. Tested and CH and HW worked fine when selected seperately. Now he's telling me that same problem is happening again with radiators getting hot when HW only selected. Any thoughts?

Thanks
 
Quick update for this problem that started a few weeks ago. When heating channel off and and hot water selected the radiators get hot. We put this down to a faulty zone valve on the CH. Fitted two brand new zone valves this morning. Tested and CH and HW worked fine when selected seperately. Now he's telling me that same problem is happening again with radiators getting hot when HW only selected. Any thoughts?



Thanks

everything working as should? eg pump coming on with boiler etc? zone valves working
 
If your confident the controls side is functioning correct as Corbs said then it could be a plumbing issue, reverse circulation or cylinder isn't the last "T" on the return to the boiler.
 
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