CH system - ground floor flat

[snapjack]

Hi - I have looked through your forum and can't find what I need to ask, but apologies if this has already been posted elsewhere.

I wish to install a multifuel boiler (possily a charnwood Cove 2B) in a ground floor flat. I obviously have no loft space and a maximum ceiling height of 2400mm.

I wish to run underfloor heating in the bulk of the flat (kitchen/diner, utility, Bathroom, small bedroom and hall), all on solid floors prepared ready to accept UFH, and radiators in the remaining rooms - master bedroom and lounge (suspended floors) bedroom 2 and porch (solid floors)

I have one main bathroom with bath and shower mixer and one en-suite with thermostatic shower and would like mains pressure hot water.

I have a potterton promax combi HE (24kw) which I only wish to use as back up, and not as the main source of heat.

I would like the facility to add solar water heating into the system in the future.

I was led to believe that as long as I had a large heat leak radiator from the multifuel boiler and if I fed the multifuel boiler (and the gas boiler) into a thermal heat store with an F & E tank above the store, I would be able to run the above system all on one floor level.

I have now been told the thermal store must be located above the boiler(?) and an F & E tank above that. Obviously, this is not possible.

Can anybody please advise?

Many thanks

 

[GavThePlumber]

Have you had permission to run a flue external to the building or do you have an existing chimney?

 

[snapjack]

yes, pre 1965 existing chimney in sound condition.

 

[Tibbot]

You have to provide an open gravity circuit at all times which means siting stores/cylinder or rad above the stove.

 

[snapjack]

I can install a radiator above the top of the stove, just not a thermal heat store with an F & E tank on top of that.

The charnwood stove will back on to the bathroom, and I can install a large heat leak radiator/towel rail up to 2400mm high in there if needs be. I was originally told by an engineer who sells multifuel stoves, boilers and excel thermal heat stores that this would be sufficient.

Thanks

 

[Tibbot]

It's not good enough to guarantee a circuit, It 'may' work but you'll be taking a chance and an expensive one at that. The stove is uncontrolled heat and mustn't boil.

 

[snapjack]

So are you saying thebottom of the vented mains pressure thermal heat store needs to be located above the top of the multifuel boiler in order for this system to work?

Thanks

 

[Tibbot]

Centre of stove to centre of store coil minimum 1m but preferably 2m. Same with heat leak rad. You could of course pump the circuit to the store and just have the heat leak rad on gravity though it could have to absorb 10-25% of the stove output (depends on makers instruction). It will also then leave a very tight space for a safety vent. In short I don't think it's do-able within 2.4m floor to ceiling.

 

[snapjack]

Thanks, sort of see what you mean, (sorry, very minimal female knowledge). A bit gutted as I was previously led to believe (by hetas heating engineer) that the thermal store would make it all possible, and I really wanted to use a multifuel boiler as opposed to the gas boiler.

I am seeking specific advice from charnwood with exact building dimensions.

The next most important thing to me is mains pressure hot water, which I can't achieve with just the combi. So, is it feasible to purchase a thermal heat store, connect the combi to it to provide the UFH, 4 rads and mains pressure hot water? I could then install a stove instead of a multifuel boiler where originally intended.

Really appreciate the advice