Find out how runnng out of hot water may be caused by a bad gas valve. Learn why it may be smarter to replace your older water heater instead of replacing the gas valve if your shower water is slow to get hot in the morning.
LESLIE: Alright, if you’ve got a hot water heater that’s not doing the job for you then you might be like Ron in Illinois. Tell us what’s going on.
RON: I’ve got a hot water heater  that’s been in the house since ’99 and oftentimes, intermittently, first thing in the morning it is not fully hot when we turn the water on. We have to have the shower turned fully on to hot. And other times it works fine. And I was wondering if it could be a fill tube that deteriorated or possibly the gas valve.
TOM: Alright, so it is gas?
RON: It is gas. Natural gas.
TOM: Alright. Forty-gallon gas-fired water heater?
RON: That’s correct.
TOM: We’re not talking about the issue of waiting for hot water in the morning like in your bathroom, are we?
RON: No, that’s correct. After the water gets up through the pipes it has to be turned fully on to have the hot water but not always.
TOM: Not always. Hmm. OK. Well, it sounds to me like you have a bad thermostat on the gas valve. Obviously it’s not performing consistently. You know, a gas water heater, Ron, is pretty simple. It doesn’t have a lot of moving parts. And if it’s behaving erratically like that, then most likely the thermostat, which controls when the gas valve comes on and off, is probably bad.
LESLIE: Now the thermostat, Tom, that’s something that’s on the water-heating unit itself?
TOM: It’s actually built into the gas valve.
LESLIE: Now is it something that – I mean he said 1999. So we’re at almost – you know, it’s ten years …
LESLIE: … and that’s kind of the life span .
TOM: Well, you know, most water heaters are going to have like around a ten-year warranty but generally we’re concerned more about the tank than the valves. But sometimes those valves do go bad and it sounds to me like that’s what’s going on here. Now your options are going to be whether or not you replace the valve or you replace the water heater and, Ron, with the age of this thing, I wouldn’t want to tell you to put too much money into it. So you may be better off just replacing the water heater .
RON: I see. (inaudible at 0:04:17.1)?
TOM: (overlapping voices) Because I mean, what are you going to get out of it? Maybe, if you’re lucky, another five years? I just hate to see you replace that valve and then a year from now the thing leaks again because, frankly, by the time you pay the plumber to come out there and replace the valve it’ll probably cost you another 100, 150 bucks to have him replace the whole water heater.
RON: OK. That’s not what I wanted to hear. (Leslie chuckles)
TOM: I know, I know, I know. It’s like we give you tough love here, Ron. (Tom and Ron chuckle) OK? We do tell you what you need to know. Thanks so much for calling us at 888-MONEY-PIT. 888-666-3974.