Replacing a Hot water cylinder?

[johnsculp]

Hello.
Have a small cottage that had electrics rads in. I want to get a wet central heating system put in. The hot water for the cottage comes via a heating element in the cylinder and the occasional use of a wood burning stove which is plumbed in to heat water as an alternative.

Can this existing cylinder be used in the new CH system? Could the wood stove be disconnected and the cylinder hot water heated via the new CH but not having top take the original tank and expansion tanks etc, out? The system at the moment is all gravity fed. The new central heating will either be oil or biomass.

 

[ambrosia]

yes, if its got a coil in the cylinder it can be done, but if its gravity its gonna be old

if youre starting from almost scratch and if you have okay mains pressure just go for an unvented system, with a new cylinder

you can get cylinders with more than one coil so you can run biomass and oil at the same time

 

[Ermintrude]

You could be really clever and mix solid fuel and bio mass or fit an aga.

 

[SimonG]

In answer to your question yes.

 

[Dotty]

So you want to convert your radiators and reuse your cylinder.

There's more involved than you think and trying to be cheap at the off won't do you any favours.

I'm out.

 

[johnsculp]

Thanks for replies, will think on these.

 

[Centralheatking]

Hi john your question is often asked here - i can see your motivation.

Using uncontrolled heat sources ie wood/coal needs VERY careful design - I would
get a HETAS engineer in to go over your plans - and pay him for his time.

I am at present very reserved over setting up a wood burner system - the price of
burning timber has outpaced all other fuel over the last year only because everybody
wants it for their stove etc - In fact thats why Tommy and I bought 5 acres of woodland
next to a motorway for £5000 recently cause there is £15,000 of mature stand to be felled.

Selling biomas seems good to me buying it not so good - If Eddie Stobart is dealing in it its got to be a massive price hike .............Centralheatking

aol iel

Hello.
Have a small cottage that had electrics rads in. I want to get a wet central heating system put in. The hot water for the cottage comes via a heating element in the cylinder and the occasional use of a wood burning stove which is plumbed in to heat water as an alternative.

Can this existing cylinder be used in the new CH system? Could the wood stove be disconnected and the cylinder hot water heated via the new CH but not having top take the original tank and expansion tanks etc, out? The system at the moment is all gravity fed. The new central heating will either be oil or biomass.

 

[johnsculp]

Yes CentralHeatKing ref Stobart and biomass fuel, good idea to buy a woodland for that price.

We are at the point where we need to replace a very old Rayburn with a clogged up 8mm microbore system approx 25 years old in the main house and this cottage I referred to above to be changed from Econ 7 heating as those electric heaters are 25 yrs old also. So the possible options we have are a complete new wet system for both properties or x2 seperate ones - running off a large 50KW oil utility boiler or a Dual Log & Wood pellet 50kw boiler.

The biomass wood boiler has the attraction of Government money for possibly 20 years but are very expensive to install in the first place, probaly x15 the price of an oil boiler. Yet that Govt RHI money would be paying for the system, then eventually most of the fuel/servicing for the 20 year span.

Yes wood will increase in price probably pegging the oil price (17p/ltr to 65p/ltr over 11 years here) eventually but we do have land here that I can set aside for SRC to come on stream in 5 years, the oil is very convenient but wood probably has more security of future supply at a reasonable price out here in the sticks.

So the replacing of cylinders in both properties has to be considered and one big 300 ltr mains fed indirect cylinder could be the best option with a recirculating pump - but we do have a fluctuating water supply pressure here to serve both properties coming off x1 inlet pipe - so showers in both properties at same time could be tricky? hence the Q could we keep our cylinders in one or both properties? as that stored water and gravity feed works well for us.

 

[Centralheatking]

Hi johnsculp -
I like your post its way beyond the usual 'armchair' stuff I have dealt with over the past few years
and would be keen to tag along with your project - send me a private msg - and if your in our radar area who knows.

You can get a 'woodland improvement grant' or something called like that - thats we are
doing with our patch in due course after we have cleared it next summer/autumn

Centralheatking.

 

[Howsie]

You want stored water and a larger separate thermal store. Get someone in who know what they are talking about.

 

[Killy Bing]

Where are you based?
sort of thing that some of us like getting our teeth stuck into!

 

[Centralheatking]

Yes Killy b - this looks like a good project to me
we can all have some input Mind you Croppie is out
but will be watching no doubt - CHK

Where are you based?
sort of thing that some of us like getting our teeth stuck into!

 

[johnsculp]

Yes Killy b - this looks like a good project to me
we can all have some input Mind you Croppie is out
but will be watching no doubt - CHK

We are based in Ayrshire and will have to do some of the basic work ourselves, two quotes from local plumbing firms for installing 21 radiators with TRV's, x2 zone valves, x2 programmable thermostats, x1 pump, x1 recirc pump came in at £10k & £11.5k plus VAT. This was without any Boiler, just for fitting the radiators, pipes and stats, those prices are too much for me so its a part DIY job. We have a friend who is a plumber on board to come in later this week to help out on adhoc basis.

Current thinking as of today is for cottage system to dispose of the direct vented hot water cylinder that the small wood stove and immersion heat directly. Then replace this with a new indirect cylinder with the new CH going to the coil on a zone valve and the existing little wood burner stove being plumbed back into the new cylinder as a direct system - as it is now. So need a cylinder with x2 tappings at 28mm for the direct heating wood burner and a coil for the indirect heating and an immersion boss. The main boiler is still to be decided upon but these Austrian biomass systems with 3000 litre thermal stores can come in a £35 - £40k fully installed with hopper for pellets, whereas the Worcester Bosch oil burner is approx £2k.

Wanting to have towel radiators and hot press cupboards on all year in both properties, so looking at a series of zone valves to facilitate.

 

[solutions]

Is ground source heat pump not an option? With a heat store you could have any potential mix of renewables and conventional fossil fuels providing the heat input.

 

[Centralheatking]

Hi John,

Before you set off down any given route have a look at 'A.E.C.B' - the association for
the environmentally conscious building and their magazine -

1. Back issues would be in 'Building for A Future' magazine - you might even read my articles !
2. it has been renamed recently - 'The Green ?'

There will be massive amount of practical info here and based on actual installations


CHK

 

[johnsculp]

Will look at that site CHK.

Thinking maybe a Heat Exchanger plate off mains water could be an option instead of a cylinder as an easier solution, albeit more expensive than tank.

Started hanging my radiators and some pipe runs, whilst mulling the HW options over.

 

[Centralheatking]

I know a really good Plate Heat Exchanger producer - they are really quite sensibly priced
considering what they do - our business mgr researched them last year for another
purpose but you are welcome to the info - send me pvt msg CHK

can you put up a design of what your attempting so we can all help ? ChK

 

[Ermintrude]

Thermal store open vent with mutipul inputs and an unvented cylinder inside that ? Some one should design an off the shelf one...... Oh ACV have . Get rep out to see you they will spec whole set up for you.