Water heater making sound like air compressor "blowoff" , couple time daily

Discussion in 'Off-Topic' started by RogueRose, May 18, 2016.

  1. RogueRose

    Thread Starter Member

    Oct 10, 2014
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    I have an air compressor that when the pressure gets too high a valve cracks open and pressure drops very quickly and it is really loud. My hot water heater seems to be doing something similar and IDK where to start looking for a cause. On top of the noise there is water that either sprays from somewhere (it is on the walls) and the drip pan fills up to almost over flowing (2" deep). I have a well and what I think is a pressure tank in addition to the water heater (it is a vertical tank with a domed top).

    I'm not real clear on how this system works so any explanations would be great! Thanks!
     
  2. geekoftheweek

    Member

    Oct 6, 2013
    42
    2
    There should be a pressure relief valve either towards the top on the side or on the top of your water heater. There should be some sort of spring loaded handle to open the valve to make sure it's not plugged. The vertical tank with a domed top is a pressure tank. I would look for the pressure relief valve as I feel it's most likely your problem... anything else would cause a flood!!
     
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  3. crutschow

    Expert

    Mar 14, 2008
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    Sounds like either the water heater pressure relief value is bad or the water pressure is too high from the well pump causing the relief valve to open.
     
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  4. geekoftheweek

    Member

    Oct 6, 2013
    42
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    Just to give you a basic layout... between the pump and your pressure tank is a check valve so that water will only flow one direction. On an in ground pump the check valve will be on the pump itself... on a jet pump it's usually on the pump at the inlet port. There's going to be a pressure switch somewhere close to the pressure tank. If I remember right it should turn on around 40 psi and off at 60 psi. If you're lucky there's a gauge there too. The pressure tank itself it more or less a balloon inside a metal case. There should be a small compressed air charge too that the bladder expands against to create the water pressure. The basic water heater has an in and out port along with the pressure relief valve. The valve should have marked on it what pressure and temperature it's supposed to open. It will open if the water gets too hot (too keep it from turning into an exploding boiler). The pressure should be somewhere between 75 to 150 psi and the temp around 200 degrees F from what I've dug up real quick.
     
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  5. #12

    Expert

    Nov 30, 2010
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    A lot of cheapskates try to not install the air tank. If they are lucky, there is enough expansion room that the pump doesn't cycle on and off. At one house, the pump would run correctly if the garden hose spigot was open because the garden hose allowed enough elasticity to hold pressure. When the hose spigot was shut, the pump would cycle every 3 or 4 seconds. Then, sometimes the bladder in the air tank ruptures and the air tank fills with water. That and a check valve will make the water heater have no place for the water to expand as it heats. In my house, I installed extra vertical pipe that goes nowhere in several places. That pipe is full of air. It's called a water hammer but that's the opposite of what it does. It kills the water hammer effect by allowing an air column for the water pressure to bounce into.

    Turn off your water pressure and drain the house. If you have any air hammer columns installed, they will fill with air and allow some expansion when the water heater does its heating job.
     
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  6. tcmtech

    Well-Known Member

    Nov 4, 2013
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    Sounds like either your pressure tank lost it's air charge and the expanding hot water has no place to go so it pops the T/P valve or the thermostat on the water heater is stuck on and it keeps heating up until the T/P valve lets go due to tank over heat.

    Either way, you have a serious and likely dangerous problem with your plumbing that needs attention now! :eek:
     
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  7. #12

    Expert

    Nov 30, 2010
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    And then again, my partner in crime had me going all over his water heater wiring, thermostats, and heating elements, when it was a bad pressure valve.
    That's why I never completely believe a customer. Even a good technician can lead me down a false path if I trust him.
    I have never seen a water heater overheat and blow the valve, but I hear its a huge mess. If that's true, and you're just leaking a little bit, you either have no air tank (that works), no air reservoir on the heater side of the check valve, or you have a bad safety valve on the heater.

    I kinda doubt a real overheat. They don't just piddle a little bit when that happens.
     
  8. shortbus

    AAC Fanatic!

    Sep 30, 2009
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    If you don't already have Farmers Insurance you should since they've already seen this. If you don't get it fixed this may happen -
     
  9. tracecom

    AAC Fanatic!

    Apr 16, 2010
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    It is also possible that the air reservoir in the outside water tank has too much water in it. You can drain it and let the pump refill it to reinflate the air reservoir.
     
  10. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    Sounds to me like the tank is simply overheating causing the pressure relief vent to operate and expelling hot water in the process..
    Same just happened to the water heater in our vacation house..
    Replaced thermostat and problem solved..
    It would occasionally go faulty and not shut down one of the heating elements..
     
  11. RogueRose

    Thread Starter Member

    Oct 10, 2014
    189
    4
    Thank you for all the replies.

    I looked at the top for the relief valve and it seems fine. I pulled the 2 covers off the side and adjusted the temp down to a lower temp in hopes that if something is really wrong then it might give some time.

    I think there is something with the pressure tank that I have to look at.
     
  12. wayneh

    Expert

    Sep 9, 2010
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    My gas water heaters will blow off "steam" when they collect enough scale inside. The scale gets so deep that it covers the thermostat probe, which is a few inches off the bottom. That causes a large lag time in the feedback loop, so the gas stays on way too long and boils off some water before the thermostat sees the heat and shuts off the gas. The release valves function as they are supposed to and prevent anything worse. After a while, this will wear out the release valves.

    The solution is obviously to clean out the tank. That's a PITA. My chunks of scale are too large to come out the tank's drain spigot, so I usually have to remove the entire spigot assembly, add water from the supply, and let the scale pour out the larger hole. Obviously you have to do all this after it has cooled down and the pressure has been released.

    A citric acid wash would complete the descaling but I've never been able to find a good source of that much citric acid. I've just lived with getting the big chunks out.
     
    Last edited: May 18, 2016
  13. cmartinez

    AAC Fanatic!

    Jan 17, 2007
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    That's very interesting ... how do you prevent water from building up over time inside them? That is, there is no such thing as a perfect seal, and with enough time the air will leak out... unless of course, you're talking about years and years. Anyway, do you purge your house's pipes every once in a while?
     
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  14. cmartinez

    AAC Fanatic!

    Jan 17, 2007
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    Was the relief valve wet when you checked it?
     
  15. #12

    Expert

    Nov 30, 2010
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    I don't. That's why I said,
    Toro Mierda. Every air conditioner and refrigerator is hermetically sealed, and they can last for decades without leaking an ounce. My water columns are soldered shut at the top, and they will last for decades.
     
  16. cmartinez

    AAC Fanatic!

    Jan 17, 2007
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    Yup... that's the answer that I more or less was expecting, but it's good to hear it from someone who's experienced.
    But my doubt was raised because water pipes are normally threaded, and not not soldered (welded?) shut.

    and btw, the correct way to say it is Caca de Toro ... although it's not more polite :D
     
    Last edited: May 18, 2016
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  17. #12

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    Nov 30, 2010
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    I didn't know, "caca" was a Spanish word. Thanks for the education.:)
    I was using what I was taught by a fellow I worked with in 1974.
    I don't allow threaded connections in a refrigerant system. The pressures are too high and a Freon leak is way more of a disaster than a water leak. Even if threads are provided, I braze them shut (94% copper, 5% silver, 1% phosphorus). That's the end of that opportunity for a leak!:cool:
    The only threads I allow in a copper pipe water system are the places where the water meets an outside agent like a hose spigot or a water heater.
    As for iron pipes? Lots of them are threaded and they seem to last just fine. I know for a fact that there is a union in the iron pipe to my house that has been there since 1959 and it still doesn't leak. Your beliefs make me wonder about the quality of materials you have available to you.
     
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  18. #12

    Expert

    Nov 30, 2010
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    I have a thought. A water softener takes about 6 weeks to become completely effective because that's how long it takes to leach the chunks out of the water heater. I was thinking: "Rent a water softener for 2 months and your water heater will be pristine on the inside." I know because I've autopsied at least 3 water heaters that lived with softened water and died of a leak in the tank. The price is one thing, the inconvenience is another thing, so I don't know if this idea is reasonable.

    "Hey, Culligan man!"
     
  19. cmartinez

    AAC Fanatic!

    Jan 17, 2007
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    Yeah, down here most water pipes (old ones, that is) are made of galvanized (zinc plated) steel. And back in the day that sort of process was not a high quality one... the plating always flaked off. So many old buildings down here have leak problems.
    Today, most houses are built using PVC pipe instead (although galvanized steel piping is of a much higher quality now), which I don't like either, because people tend to use the thin-walled glue-together type, instead of the threaded thick-schedule one. It breaks easily (for my taste) and is affected by the sun's UV when installed outdoors. Manufacturers say that they come with a UV protective coating, but I've seen those pipes being affected after only 5 years of laying in the sun.
     
  20. wayneh

    Expert

    Sep 9, 2010
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    Yes, softening makes a big difference. If I am diligent about keeping my softener filled with salt and functioning, my water heaters go for years between cleanings. When the softener goes down, the lime scale accumulates quickly, and my well water is not particularly hard.
     
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