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15mm fittings on 8mm microbore CH?
ed110220
Posts: 1,629 Forumite
I need to replace a bathroom radiator with a heated towel rail type radiator and also put in a radiator in a room that doesn't have one at present. The central heating system uses 8mm microbore pipes as there is no room for standard size pipework between the downstairs ceilings and first floor steel beams. At the moment the bathroom radiator is an old type where the inlet and outlet are at the same corner so the pipework needs moving slightly.
Is it possible or advisable to use 15mm pipe for the last part of the pipe run between the floor and the radiator? I was thinking it may make it easier. I also hate the look of exposed 8mm pipework as it bends and doesn't stay straight and generally looks untidy.
I got the idea from my neighbours who seem to have done this with some of their radiators (also microbore system).
Is it possible or advisable to use 15mm pipe for the last part of the pipe run between the floor and the radiator? I was thinking it may make it easier. I also hate the look of exposed 8mm pipework as it bends and doesn't stay straight and generally looks untidy.
I got the idea from my neighbours who seem to have done this with some of their radiators (also microbore system).
Solar install June 2022, Bath
4.8 kW array, Growatt SPH5000 inverter, 1x Seplos Mason 280L V3 battery 15.2 kWh.
SSW roof. ~22° pitch, BISF house. 12 x 400W Hyundai panels
4.8 kW array, Growatt SPH5000 inverter, 1x Seplos Mason 280L V3 battery 15.2 kWh.
SSW roof. ~22° pitch, BISF house. 12 x 400W Hyundai panels
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Comments
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You just need an 8mm x 15mm reducer. Fairly straightforward.Eat vegetables and fear no creditors, rather than eat duck and hide.0
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You just need an 8mm x 15mm reducer. Fairly straightforward.
Thanks, that was what I was thinking of. I was just wondering whether it would disrupt the flow pattern significantly, but I guess not as the 15mm pipe at the end of the 8mm would be fairly short.Solar install June 2022, Bath
4.8 kW array, Growatt SPH5000 inverter, 1x Seplos Mason 280L V3 battery 15.2 kWh.
SSW roof. ~22° pitch, BISF house. 12 x 400W Hyundai panels0 -
I converted to 15mm from micro bore years ago when I repositioned the bathroom rad. No problem at all, you just need to buy the correct reducers.I can afford anything that I want.
Just so long as I don't want much.0 -
The difference between genius and stupidity is that genius has it's limits. - Einstein0 -
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but I doubt OP would be impressed if such was recommended to them.

Cheers
R , but not recommending to the OP, if i was? i would recommend he used 15mm chrome plated pipe into the rad valves, then used a compression reducer under the floor, or somewhere not visable
A thankyou is payment enough .0
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