Hot water heater relief valve

[rlb]

Short story, I was doing some plumbing things and I heard my hot water heater making some funky noises. I got a little paranoid and decided it was time to check on the pressure relief valve because in all of the years I've lived here I've never done that.

I exercised the valve and some pretty rusty water came out, but I let it flow enough until everything ran clean. The valve flows well and seals completely when I let go with a lever.

Is there anything else to it? Any other reasons to be concerned? If the valve flows when testing it's doing its job, correct?




A little more backstory: I had to replace the hot water shut-off valve under my kitchen sink. Rather than turning off all of the water to the house, I just turned off the water supply to the hot water heater. I left a bathroom spout open to avoid any water drips because all of my valves are old and leaky (including the supply valve to the hot water heater).

I turned the water on and off like this a few times, and it caused the water heater to fire. I happened to be standing next to it while the flame was on (but the supply was shut off and a bathroom hot water faucet was open). It was making some glugging and thumping sounds. I think the combination of the heater being fired with an open faucet nearby (essentially an air vent) was causing it to make some funky noises.

 

[ryderX]

How old is the water heater ? P&T valves are relatively reliable though usually when folks test them they never reseat. If it’s not weeping you’re good to go.

 

[one piece crank]

I have found cycling the over-pressure relief valve is a risky proposition, especially if your hot water heater is “old”. Easy to get one of those rust particles preventing the valve from sealing up.

In our current house I replaced our first water heater at 14 years, which was pushing it. Now I replace the water heater as soon as the warranty is up, especially since the damage potential is High if it started to leak, and water heater longevity is questionable anyway…

 

[rlb]

I have found cycling the over-pressure relief valve is a risky proposition, especially if your hot water heater is “old”. Easy to get one of those rust particles preventing the valve from sealing up.

In our current house I replaced our first water heater at 14 years, which was pushing it. Now I replace the water heater as soon as the warranty is up, especially since the damage potential is High if it started to leak, and water heater longevity is questionable anyway…

Its cycled, so no undoing that. It blew out all of the chunks and is sealed up now, so that part is OK.

My concern is the water heater exploding, given the noises. I'm just trying to make sure that if the valve manually operates, it will also operate in a high pressure situation.

The heater has run a bit now and no more noises. Also the tank looks fine externally, and the hot water pressure is normal. I think I'm in good shape...

 

[one piece crank]

Sounds like it’s functioning normally. Check the date code on the data plate. If it’s 6-years or older replace it.

 

[qclabrat]

Sounds like it’s functioning normally. Check the date code on the data plate. If it’s 6-years or older replace it.

Wow, only 6 years? I usually change them every 12-15. Recently changed the controller on an 8yo unit and flushed the tank twice to remove particulates. The relief valve leaked a tad the first time but after a couple flicks of the lever it stopped. At 2k each, I can't afford changing every 6 years. I'll likely switch to tankless the next go around.

 

[Mahnken]

Change your anode rods for a longer lasting water heater. My neighbor has had the same water heater for over 30 years. He just changes out the anode every few years.

 

[rlb]

Sounds like it’s functioning normally. Check the date code on the data plate. If it’s 6-years or older replace it.

It's 10+ years old. Not sure I have it in me to replace it while it's still working (unless you mean the valve?)

 

[shrpshtr325]

Sounds like it’s functioning normally. Check the date code on the data plate. If it’s 6-years or older replace it.

thats insanely frequently, but its your money. spend it how you want.


that said there is a maintenance item that most people must not know about since i never hear about it. flush the water heater to rinse the sediment off the bottom. the sediment causes it to sound like popcorn or rocks rolling around when it is on. I have been told to do that naywhere from monthly to yearly to 5 years, i tend to do it yearly just to cover my ass.

 

[Patrick]

My first tankless lasted 25 years. The valve that varied the gas with the water flow stb. Bosch gave me a deep discount on a new one. I'm a fan

 

[Santapez]

My first tankless lasted 25 years. The valve that varied the gas with the water flow stb. Bosch gave me a deep discount on a new one. I'm a fan

I was going to ask thoughts on tankless for reliability as opposed to a tank. It seems crazy to me that an appliance that should be simple dies in roughly a decade with the symptom being a water leak possibly doing a lot of damage. Mine is a year old and I'm already worried...

Tankless also seems really nice for being able to install yourself as it doesn't seem as large/bulky as a tank style if stairs are involved.

 

[Mahnken]

My first tankless lasted 25 years. The valve that varied the gas with the water flow stb. Bosch gave me a deep discount on a new one. I'm a fan

13 year old tankless working quite lovely in the new house. Really glad I didn't upgrade the 12 year old water heater in the old house before moving 😂 it was on the to do list.

 

[one piece crank]

thats insanely frequently, but its your money. spend it how you want.
.

Yes, I agree. But the one I replaced at 14 years was on borrowed time. And the second one was replaced at 8 years, flushed once a year and all that rusty sediment was once part of the inside of the tank. So, better safe than sorry, and about $1100 all said and done.

 

[Patrick]

I was going to ask thoughts on tankless for reliability as opposed to a tank. It seems crazy to me that an appliance that should be simple dies in roughly a decade with the symptom being a water leak possibly doing a lot of damage. Mine is a year old and I'm already worried...

Tankless also seems really nice for being able to install yourself as it doesn't seem as large/bulky as a tank style if stairs are involved.

It is harder to install because of the venting (and possible supply air) requirements. It can't use a chimney because the exhausted air isn't hot enough.

That being said, it isn't "that" hard.
3/4" water feed, and 3/4" gas line. 4" stainless vent. Depending on other appliances in the house, may need to upsize the gas meter.
There is a form to submit.

 

[Mahnken]

I was going to ask thoughts on tankless for reliability as opposed to a tank. It seems crazy to me that an appliance that should be simple dies in roughly a decade with the symptom being a water leak possibly doing a lot of damage. Mine is a year old and I'm already worried...

Tankless also seems really nice for being able to install yourself as it doesn't seem as large/bulky as a tank style if stairs are involved.

I like the idea of a pan underneath with a water sensor that automatically shuts off the supply valve when it senses water.
The tank will also last much longer than a decade if you change the anode rod every couple years, I think they're only about $20.
I love the tankless though. Hard to beat endless hot water. And they typically last at least 20 years. If you have gas, making the switch would likely require a new, different type of flue vent. Otherwise the piping and electric are the same and it saves a bunch of space. Ours is in a cabinet in the laundry room.

 

[Santapez]

The laundry room setup is pretty interesting!

@Patrick Yeah I should have mentioned it's probably an easy install for me with the venting. I think with the current location of the tank I can just go up 2-3 feet and pop out the exterior wall with the PVC piping.

I know upsizing the gas line can be a concern but it is fed right off the main and I can't imagine the BTUs are higher than my furnace. And if I ever replacing my furnace I'm going down 20kBTU or so on a new one.

For the time being I'll probably get an water alarm to put on the floor and change the anodes every few years. If I see water (or hear an alarm) I'd just shut the main water valve.

 

[JerseyPete]

What is the general thought on induction tankless water heaters? No gas, no vents, but electric can be costly.

Instant Water Heater | ElectriCast™

The ElectriCast Induction Instant Water Heater provides instant hot water to homes and businesses on demand, powered completely by electric.

electricast.com

 

[rick81721]

What is the general thought on induction tankless water heaters? No gas, no vents, but electric can be costly.

Instant Water Heater | ElectriCast™

The ElectriCast Induction Instant Water Heater provides instant hot water to homes and businesses on demand, powered completely by electric.

electricast.com

This would be our only option - all electric

 

[Patrick]

This would be our only option - all electric

Big propane tank to heat that pool in the "winter" !
Would also run the b/u generator.

This electric is a point-of-use system ??? prob 1.5gpm at best.
Would need multiple?

 

[rick81721]

Big propane tank to heat that pool in the "winter" !
Would also run the b/u generator.

This electric is a point-of-use system ??? prob 1.5gpm at best.
Would need multiple?

Some bury a tank in their yard to fuel a gas stove and generator. Our plan is to go solar with sufficient battery storage to run everything.