I live in California and I am wondering if I can use PVC to exstend a HOT water branch (underground) to my detached garage, about 20 feet. I know that it does not meet code. I am just wondering if the PVC that is rated at 73f will hold up. I have talked to plumbers that have said yes but others that have said no. Would anyone with some "real" experiance with this please reply. Thank you.
The 73 degree temp is based on working pressure of pipe. When you exceed that temp the pressure rating of the pipe degrades rapidily. Further over that temp the pipes' composition also degrades. Bottom line how soon do you want to dig up the pipe and how often. Look at CPVC which is rated for higher temps better yet bite the bullet and put in copper and not worry about it again. I also bet the plumbers who told you it would work are still laughing. From a bona fide do it youselfer do you really want to dig that trench again. Also a 20' hot water line through the ground unless insulated very well will be luke warm water on arrival and you will waste a lot of water before it gets to you . A small hot water heater in the garage will give you hot water and you can put a switch on it to turn on and off. With the heater in the garage you can bury your PVC and not worry.
Joe, thank you,you bring up some excellent points. I recently had to dig up my patio in order to replace a gas line and while I was at it I figured why not just run the h20 out there. I went ahead and purchased the copper to do the job this past weekend but got delayed (whats new)Now I think I will just run the cold out and save up for the heater.