Re: Low hot water pressure, cold is good
It's good to hear you got it fixed. For everyone else reading this...
Just a note on the pressure gauge: the pressure you note is only relevant while water is flowing. With no flow, your pipe could be nearly blocked and it will show about the same pressure as anywhere else in the line. (Elevation matters -- every 2.31 feet of rise results in 1 PSI of static pressure drop.)
With the gauge attached to the drain on the water heater, open a bathtub hot water tap full flow. If the blockage is on the cold water side of the water heater, you should see a noticeable drop in pressure. If the blockage is on the hot water side, you will see little drop in pressure.
Note that most sink faucets, even with the aerators removed, will limit the flow of water -- the hole in the valve might be smaller than the hole through the blockage in the pipe, so opening a sink faucet may not prove anything.
The "Senior Member" designation under my name doesn't mean I know a lot, it just means I talk a lot.I've been a DIYer since I was 12 (thanks, Dad!). I have read several books on various home improvement topics. I do not have any current code books I can refer to. I was an apprentice plumber for two years.