plastic pipe running beside HW cylinder and boiler

15 Oct 2006
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United Kingdom
I know from other posts that at least 300mm of copper pipe must be used when connecting plastic pipework to a boiler, but what if you are just running pipes from the hot water Cylinder past the boiler, and not connecting to it. Can I run plastic pipe and plastic pushfit connections? or should it be copper and compression? Pipework will pass within 100mm of HW cylinder and 200mm of the boiler.
Many thanks
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Which boiler? Which part of the boiler? What's the temperature at the proposed pipe position? What's the ambient temperature?
In almost all cases with boilers made during the last 10 years you can run a plastic pipe within 50 mm of the case PROVIDED placing something physically there does not impinge on the maintenance access space required for the boiler.

Many boiler makers require at least ONE meter of copper pipe on the heating flow and return.

If the cylinder is foam insulated then any plastic pipes can touch the insulation from a heat point of view but as some plastics can act strangely its best not to let it touch.

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Thanks, Softus and Agile.

The boiler is an Ideal Mexico RS Super 125. It is approx 80mm from the wall. The pipework will be 100mm from the front left corner of the boiler casing, slightly in front of it. Next to the pipe are the flow and return pipes for the CH. The ambient temperature is about 25c

With regards the HWC. The pipework will be within 50mm of the insulation, but I will ensure it does not touch any part.

Thanks again for your advice

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