Combining multi fuel boiler and oil

nophd08

Hi all, my plan is to fit a multi fuel boiler in my shed 20 metres from house and connect to pipework on oil module outside house, boiler will be 30kw like this one http://kotlospaw.com/en/uks-g#p=s1
Few different plumbers have looked at it.
One wants to install with 1500L buffer, open vent.
another with no buffer, open vent, various safety features, mechanical cooling loop in case of power failure.
Another with heat exchanger/system link with open vent so that solid fuel boiler is seperate from sealed system.
I like the idea of the heat exchanger set up,
also my house was plumbed (12 yrs ago) with acorn pipe and the last plumber said this wouldnt be suitable to directly connect solid fuel to. ie higher temp.
So basically, flow and return from house to heat exchanger in shed in underground insulated pipe, and flow and return from boiler to heat exchanger open vented etc.
Apologies for long post, any feedback welcome.

jimjimt

Here is what the manufacture recommends.

http://kotlospaw.com/en/automatyka

I presume you have a oil boiler in a cabin pack or similar or in a small shed ?
If it is a cabin pack/module there will not be enough space to connect and control both systems correctly in the module. You just do not tee into the pipe work.

You will need highly insulated pipework from garage to house the 35euro a meter insulated pipe. Along with a 7 core 2.5mm armored cable to control your boiler and heating system.

Most solid fuel/wood gasification boilers of that sort are fitted with buffer tanks. I do believes this would be the best option for you. To get the best control you would have to get your new pipe work and cable to the hot press/heating manifolds to control your heating zones.

Or move your oil boiler to garage and attached it to the buffer tank. The buffer tank as such would be the boiler that heats your house. The oil boiler can either heat the buffer tank or directly to your house if controlled properly.

Email the boiler company directly they may have a selection of drawings that will help choose the best setup for your house.

nophd08

Thanks for reply jimjim, I have seen a few installations, with and without buffers, very straight forward. with buffer the only control was a timer on the circulating pump, the laddomat loaded the buffer when boiler temp came up.
The installation without buffer was simply T'eed into existing heating with open vent and heat dump rad. Very professionally done.
Basically its just big insulated stove that will hold enough fuel to get up to 8hrs burn time depending on size.
The insulated pipe is expensive....but.. so is a fill of oil which will be god knows what price in 5 yrs.

jimjimt

If you do go with the buffer you should consider a bit more control. As in the boiler can be controlled to heat directly into the house first or buffer first and then the house you can choose which.
The buffer is good so you can load up your stove before you go to work and and have the heating ready to go in the evening time.

Do take heed in the way the manufacturers recommends the install as the buffer also act as a heat dump for a solid fuel appliance. It is not there for no reason.

You should also install the extra wire for more control even you do just decide to tee in at the oil boiler module. You may not realize the benefits of it until you have your stove installed for a while.

eoingaillimh

Hi nophd08,

Just wondering how you got on since regarding your solid fuel boiler installation? Did you go for the buffer or non-buffer option?

I'm in a similar position to yours - considering installing a solid fuel boiler but would like to keep the oil boiler as backup if possible.

Our central heating is underfloor heating, which we can't use much anymore as the cost is prohibitive - if we were to use it for the entire heating season we would be spending close to €4k on oil per annum at current prices. As we cut our own turf, a solid fuel boiler would seem to be a much more economic option if they work like they're supposed to.