Suddenly lost hot water pressure over night only upstairs. The basement pressure is great still. Had to shut the main off 3 times yesterday because we were fixing a belt on washer, but before we went to bed, we did dishes, and all was good. Went to take a shower a few hours later and the hot water pressure is very low, same as in the bthrm sink and kitchen sink. Water meter is not running when water is off, and I cannot see any obvious leaks... any suggestions?

Suddenly lost hot water pressure over night only upstairs. You have good pressure on the cold side? Try this. Turn the water off under the bathroom vanity and open up the valve, Remove the cartridge and check the inlet poets for a clog. Now place a pan over the open valve and turn the water back on to flush out the supplies. You should see a strong stream. Reassemble and test. If the faucet's working OK then do 6the same thing to all affected faucets. Good luck. Tom