Max distance of gas boiler

ravendude

Hi,
Have an 18kw gloworm boiler, I'm wondering is there a limit on how far a boiler will pump.

We have a bit of a mad setup. House used to be oil fired so there used to be a boiler house at the back of the back garden. The boiler house used to pump water to the main house obviously.
A sunroom extension was built and they connected the old oil boilerhouse boiler direct to the sunroom. Ie. The boiler house had 2 circuit runs, one to the extension and the other to the utility room of the existing part.

Wind forward 10 or 15 years and we replaced tge oil boilerhouse with a nice tidy gloworm gas boiler in the utility room.
Problem is the gas contractor reused some iof the old pipes for the extension, so again 2 circuits, 1 all internal the the main house part, the other (the mad part) goes back out the house to the back of the back garden where the old boiler used to be (about 10 or 12 metres) then back to the extension on the far side of the house! And obviously you have a return as well! So you have an internal boiler pumping the house then pumping out around the back garden to the sunroom under the ground!
The extension part is sluggish to heat up and our bills seem a bit high.
Would the distance and 2 circuits diminish the system performance a lot? I'd say that weird exterior circuit is 30 to 40 metres in length in addition to the rest of the house!

We are doing some renovation works now to the house, so I'm wondering if it is worth the cost of getting this sorted for once and for all. Could we expect the house to heat faster and cheaper etc if we rerouted so all the pipes would be internal to the house?
Thanks!

antoinolachtnai

This definitely sounds worth doing.

It will be easier to maintain too. It's hard to know for sure that there aren't any leaks in that long, old pipe run.

Eventually this setup will give you a lot of trouble so worth fixing.

9935452

Id fix it if it was me.
If the pipes outside are gunbarrel you could be pumping heat into the ground.
I used to rent a house which took a long time to heat up and used to burn a lot of oil to heat it .
Pipe burst outside between the house and boilerhouse.
Pipe was dug up and replaced.
The old pipe was like a sieve.
Suddenly the house heated quicker and cost less to do so

DublinDilbert

Surely you could dig down just where all the pipes come out of the house and loop the pipes there rather than at the end of the garden. But I'd probably consider just plumbing the sun room directly to the house, maybe install some vertical rads.

ravendude

DublinDilbert wrote: »

Surely you could dig down just where all the pipes come out of the house and loop the pipes there rather than at the end of the garden. But I'd probably consider just plumbing the sun room directly to the house, maybe install some vertical rads.

Yep, that's what we are planning, more or less. We are building an extension and adding a new bedroom on top of the sunroom.

I expect it will be hard to connect the sunroom to the adjoining room directly as both are laid with continuous solid wood floors, - which would likely cost to pull up etc.

However, as we are building above, I am thinking we could reroute so that circuit is all in the house, but go up from the boiler, along a knee wall space above and back down to the sunroom. The wall cavities in the sunroom will be opened up anyway as bedroom is going above. Not 100% ideal, there would still be a bit of a run, though a lot shorter, but much better I expect and at least all the pipes will be in the house.

DublinDilbert

If your building above, drop down a new run into the sun room. You can get some vertical rads that can be top fed as far as i know.