New central heating system

[jimbo5050]

I am a novice as far as central heating is concerned.
I live in rural Scotland, where getting decent trades people is hard.
I am building a 3 bed, 2 bathroom extension to a croft house that has 2 living rooms, 1 small bedroom, 1 bathroom and a kitchen.
The existing house has a central heating system that does not work due to the fact that it runs of an oil conversion raeburn cooker that is just not up to the job (this also provides the hot water via an immersion tank)
I was going to install a multifuel stove with a central heating boiler but I was persauded against this idea by a couple of folk.
I want rads in each new bedroom and I thought of a couple of towel rads in the bathrooms.
One suggestion is a new oil fired boiler (which goes outside?) and works like a combi with instant hot water as opposed to a hot water storage tank.
Gas is out of the question as there is no mains and I have had LPG in the past which was a nightmare.
Also would installing the central heating be within the scope of a novice like myself (someone has suggested polypipe with the push on fittings as oppposed to traditional coppper). The inner leaf wall of the extension made from 95x45mm framework and after the insulation has been fitted there will be a 25mm gap left for services. The floor is a suspended one so pipes can be run underneath if need be.
Any suggestions will be appreciated.

 

[oilman]

I was going to install a multifuel stove with a central heating boiler but I was persauded against this idea by a couple of folk.

Don't be put off too easily. look here for starters. This is the starting point for connecting multiple heat sources.

You could supplement the Rayburn with a pressure jet boiler, and then use a multifuel stove without waterheating to give space heating for an independant heater. For the best see this (but how easy would it be to get solid fuel? As for combi boilers, there are a LOT of problems with combies in rural Scotland. DON'T touch them. Stick to a conventional boiler and tank. You are too far away to need the tribulations of a combi.

Connecting the boiler and Rayburn to the system will not need the Dunsley unit, but you will need to do some research for other methods. Installing the heating system with plastic piping is a doddle, but personally I would not hide the pipes in the structure. By all means box them in, but they may need maintaining some day, or you might want to modify the pipes.