Replacing Microbore Piping When Replacing Radiator All aspects of plumbing questions and answers, help, tips and information

[Archiethere]

Hello, I’m looking to replace a radiator in my kitchen, I’ve just renovated the whole kitchen and the old radiator in the corner is the last job on my to do list! I feel confident changing the radiator however there is 8mm Microbore piping running off of the kitchen radiator pipes which goes through a wall and feeds a radiator in my dining room. Is there a reason why I can’t change this 8mm to 15mm and have all new piping there? The radiator we have going in is a cast iron style one and wouldn’t look right with old pipes covered in paint, however to do this I would have to alter the pipes which feed the other radiator. Any advice would be greatly appreciated.

https://ibb.co/LpcwWZW

[Barbastelle]

First off we need to understand how all your other radiators are fed by.
Presuming they are also 8mm copper piping, each set of pipes (2) from each radiator should go back to an manifold. The manifold you should find is between pipes from the boiler to a single radiator connected by two 15mm pipes. I would not fit 15mm pipes from your living room radiator to your kitchen. Go back to the manifold. There may be blanked off connections you may be able to use.
I would be happier if your 8mm pipes were infact 10mm.
Hint - if micro-bore pipes get blocked use a car pump to clear blockage.
If living room are 15mm directly from the boiler you should be Ok to take off off them. but plumb so you can turn each rad. off independently with TVR valves.

[Barbastelle]

Sorry, I mean Thermostatic Radiator Valve (TRV) and not TVR as put in my reply.
These days TRV's can be fitted any end of the radiator. Inlet or outlet to suit. Just check the flow arrows.
Sometimes when replacing them it is necessary to replace the 15mm pipe tail to the copper T connector.