djdavenport
Member
I have a fairly new combi-mod unit which has been working great. When they installed it, they put in a 10 gal electric buffer tank (supposed cold sandwich cure) that the recirc system taps off from. Yesterday, while doing some routine poking around I saw that the T&P valve on the electric HW was dripping. I threw on a water pressure gauge (a cheap one and probably not very accurate) and it showed the DHW side had risen to about 110 PSI.
Normal water pressure is +/- 70 psi--which it was at the time I checked.
My questions are: 1.) Sloppy T&P valve weeping 40 psi early. Should I just ignore it (or replace it)?
2.) I know there's a lot of opinions on the internet about not needing an expansion tank with an on-demand system. (What triggers the hot water is the very thing that releases the pressure. Cracking open a faucet.) But I haven't found much about on-demand systems coupled with a small storage tank. And, would a bump from 70psi to 110psi be normal for that kind of set-up?
I don't mind putting in a tank if that's the smart thing to do. Will an occasional pressure spike up to 110psi hurt the system?
Thanks, as always, for your advice.
Normal water pressure is +/- 70 psi--which it was at the time I checked.
My questions are: 1.) Sloppy T&P valve weeping 40 psi early. Should I just ignore it (or replace it)?
2.) I know there's a lot of opinions on the internet about not needing an expansion tank with an on-demand system. (What triggers the hot water is the very thing that releases the pressure. Cracking open a faucet.) But I haven't found much about on-demand systems coupled with a small storage tank. And, would a bump from 70psi to 110psi be normal for that kind of set-up?
I don't mind putting in a tank if that's the smart thing to do. Will an occasional pressure spike up to 110psi hurt the system?
Thanks, as always, for your advice.