PVC is not suitable for hot water.

You need at least CPVC.

Plastic pipe expands a lot more than metal with temperature changes.

Put at least a U-bend in the middle of the long run to allow more movement.

This post was edited by brickeyee on Sun, May 19, 13 at 14:01

A few questions:

2. Are you certain it is PVC and not CPVC? Brickeyee is correct that PVC is not suitable for hot water - it is important to know precisely what the pipe material is.

3. Diameter of the pipe?

4. Length of the straight run?

5. Temperature of the circulating water

6. Coolest temperature to which the pipe is exposed

The correct size for an expansion loop is easy enough to calculate given the above information. Loop size will be mute, of course, if the pipe is the wrong material.

it is 1" pipe and it is cpvc..the length is at least 20 feet. it does not have a U bend. a plumber suggested some kind of flex at the intersection..whatever that means..i dont know the temp of the water, but it is the hot feed all 3 times. any further help on the "flex" or whatever that means.
Thanks

Okay, I asked the question I asked because they are ALL required in order to calculate the proper size for an expansion U for your pipe. If you can't provide those answers, nobody can help you.

This post was edited by aliceinwonderland_id on Fri, May 24, 13 at 21:33