help needed with non standard heating system

[cruelty]

hi,

system has CH & HW Zones
system also has back bolier
system has no motorized valves

so there is 2 zone time clock
1 room stat
1 cylinder stat
1 pipe stat (on back boiler flow pipe)

what i need to happen:
CH turned on = fire Boiler & Circulating pump
HW turned on = fire Just boiler
Back boiler flow pipe = fire just circulating pump

cant seem to understand how to connect without getting back feeds etc..

any help appreciated

 

[topquark]

I'm a little confused by your mention of back feeds, what type of boiler is in use (does it have separate HW and CH outputs?).

What is the back boiler feeding, HW, CH or both? I'm guessing both and you have a two coil storage cylinder? I'm off to bed, but it may help someone else answer.

 

[cruelty]

its an oil boiler with pump beside it (located in garage)

back boiler it to be used for CH & HW and yes its a 2 coil storage cylinder

thanks for your reply, any help appreciated as i need to complete job in few days :thumbs_down:

 

[topquark]

OK, if I can summarise you have:

1 x two channel programmer (CH ON, HW ON, HW OFF)
1 x room stat
1 x cylinder stat
1 x pipe stat (on back boiler flow pipe)

You have no motorised valves so you may only have one CH zone.

Do you have separate pumps for the back boiler and main boiler or only one pump ?

 

[topquark]

If I'm reading this correctly you have the following components:

View attachment 8166

 

[Dunc]

When you refer to the 'back boiler' is this a solid fuel stove arrangement where the oil boiler is used to top up the system if the back boiler isn't able to meet demand? A little more detail about how it's plumbed in would be helpful i think. If the HW tank has two coils is the oil fired boiler only connected up to one coil and no CH loop? At the moment i can't make a lot of sense of what you want to achieve. I'm assuming it's a gravity hot water system with pumped central heating?

 

[cruelty]

as i am only doing electrical side of things i am not up to speed on the plumbing end of it

@topquark: yes you are correct on:

1 x two channel programmer (CH ON, HW ON, HW OFF)
1 x room stat
1 x cylinder stat
1 x pipe stat (on back boiler flow pipe)

and yes i have only one CH Zone
there is a separate pump for back boiler


@Dunc: Back boiler is an open fire with flow and return pipes, and yes oil should be used to topup demand, i will find out more from plumber tomorrow and post it up
I do know its a pressurised system

thanks

 

[topquark]

OK so far, then the component list is correct (and piccy), we now need to know how the back boiler is connected into the system (to decide how to wire the pipe stat in).

 

[cruelty]

OK so far, then the component list is correct (and piccy), we now need to know how the back boiler is connected into the system (to decide how to wire the pipe stat in).

hey, what do you mean by how the back boiler is connected to the system? do you mean plumbing wise or electrical?

 

[topquark]

hey, what do you mean by how the back boiler is connected to the system? do you mean plumbing wise or electrical?

Plumbing wise. It would be useful if you (or the plumber) could draw a flow picture of the plumbing and indicate on it where the two pumps and two heat sources (back boiler and oil fired) are.

 

[cruelty]

i will try and explain to you now, because wont get talking to plumber until Monday

back boiler (open fire) located living room, flow and return from cylinder, pump located in hot press

Circulation pump for CH in hot press also beside cylinder which is just flow and return from cylinder

Oil Burner and pump located in garage and also a flow and return


how that helps but could be no use at all lol

EDIT: Plumber has agreed to fit motorized valve after circulation pump so i can switch it for HW or CH (ie. boiler & c.pump for CH, - boiler only for HW)

So its a standard "C" Plan at the minute

So how to add back boiler to system, knew i would get it in the end lol

thanks for your patience

 

[ufkir]

under no circumstances should a solid fuel fire be connected to an unvented pressureised system and even if it is unvented yuo ned a flow divertor

 

[ufkir]

sorry my typing mistake it should read even if its a vented system you need a flow divertor to link both systems oil and solid fuel