we have a 50 gallon hi recovery gas hot water heater originally installed in 1999. We have a little thermal expansion tank too - about 1.5 gallons. Our 4 BR, 3 1/2BA house was built in 1976 and does NOT have a pressure reducing valve. The city utility company told me the incoming water pressure in our area is 84 PSI. I have noticed our utility room floor is wet - water leaking out the Temp/Pressure Valve pipe into the hot water pan and then leaking out onto the floor - because the pan leaks and there is no drain in the floor. Yikes!
I've noticed the wet floors twice - both times after using 2 shower heads simultaneously for 5-10 minutes. (normally we only use one for about 5-10 minutes). The concrete floor looked like about 1-3 gallons of water had been spilled on it. To be honest, we don't go down in the utility room very often, so this problem may have been happening before too.
After reading several threads, I'm not sure how to narrow down the problem/fix.
1) new homes are required to put a pressure reducing valve in. Should we go ahead and do that? can a very competent DIYer do that job?
2) should we increase the size of our thermal expansion tank to something like 4 gallons? I tried that chart, but couldn't figure out what we really needed.
3) could it just be the TPV is broken? it stops dripping after a few minutes of turning down the hot water temperature and turning off the water intake to the heater.
4) could it be the temperature gague is broken? it does sound like it goes on and off when it "should".
5) the anode tube has never been replaced (7 years old). could that be causing the problem or adding to it?
6) should we just bite the bullet and replace the whole hot water heater? with what size expansion tank? I hate to dump something that big into the landfill unless it is really necessary.
7) there is no drain in the utility room (basement) floor. should we bite the bullet and dig up the concrete and install a drain to the outside? It would have to go about 20' through concrete. how much should I expect to pay for that? again, could a DIYer do it? (we used a jackhammer once!)
8) what about these new tankless units? how do I do a cost/benefit analysis of them?
thanks for sharing your wisdom and experience with me! diane bellevue, WA