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 Copper tube - odd size?
Author: JazzGuitarGimp (PA)


I am about to install an electric water heater to use as an alternate to a boiler, which is too costly to operate. The copper tubes leading into and out of the boiler measure 3/4” OD. This suggests a pipe size of 5/8”. The problem is, I cannot find 5/8” copper tubing at Lowe’s or Home Depot. Our house was built in 1953. Is 5/8” just an outdated size that is no longer manufactured?

Second question, please: I will use valves to select either boiler or electric water tank. Is it safe to leave water sitting in the boiler for a number of years?


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 Re: Copper tube - odd size?
Author: packy (MA)

you are dealing with refrigeration tubing.
a place that sells refrigeration supplies should have reducing couplings.

you can search for an additive for the boiler water but the components of the heating system would be suspect if left alone for years.

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 Re: Copper tube - odd size?
Author: bernabeu (SC)





"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

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 Re: Copper tube - odd size?
Author: sum (FL)

there are also adapter copper couplings you can get that transitions from AC tubing to water supply tubing.

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