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Ruud Monel Water Heater

scubacat
scubacat Member Posts: 6
edited November 2021 in Domestic Hot Water
My Ruud Monel has been going strong for over 60 years. Recently, the gas lines on my house were pressure-checked, and it was determined that the there is loss of pressure (6 ounces/10 minutes). So, the gas was shut off. A licensed plumber came in and replaced all of the gas appliance shut-off valves. When each gas line was systematically pressure checked, I was advised that the pressure was being lost in the line going to the hot water tank. When the water tank shut-off valve was closed, no leaks were detected. When open, the loss of pressure recurred. No natural gas smell was ever detected.
I was advised that the water tank would have to be replaced. The gas line to the tank was permanently capped. Now we have no hot water.
This water heater has been performing flawlessly for all of these years.
Now, the questions:
1) Could the fittings (downstream from the new tank shut-off valve) be the cause of the
leak, and the water tank is fine?
2) Is there something within the mechanical valve that can leak?
3) If defective, are these valves repairable?
4) If defective, is there a "universal valve", that can replace the one on the tank?


I am very, very reluctant to give up my Ruud Monel. Looking for any insight or advice that will help me with this situation.

Comments

  • GW
    GW Member Posts: 4,691
    Happy Thanksgiving, if there’s no water on the floor and no gas detection, and it’s venting properly- seems like you’re getting scammed
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    gary@wilsonph.com
  • mattmia2
    mattmia2 Member Posts: 9,574
    Is the pilot shut off? Seems like that could have a pilot that is only shut off with the manual valve given its age. Probably options to put a new gas valve on it too.
  • mattmia2
    mattmia2 Member Posts: 9,574
    Pictures would help
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,453
    @scubacat

    Yes it is likely that the piping downstream of the water heater gas cock is leaking. You just need some one that knows what they are doing.

    The correct procedure is to have someone turn the gas back on and leak test the piping with soap bubbles.

    if they red tagged the water heater you will have to have your tech call the gas inspector/gas company to get the ok to put this back in service
  • scubacat
    scubacat Member Posts: 6
    edited November 2021
    Thank you for your reply.
    No red tag by the gas company. The plumber (licensed) left it with a permanent end-cap.
    This is the tough part - finding someone who knows what they are doing.....!
    Some photos:




    I'm not giving up this water heater without a fight.



  • Larry Weingarten
    Larry Weingarten Member Posts: 3,273
    edited November 2021
    Hi, What GW said. If the heater doesn't leak water or gas, then the heater is OK. Gas pressure testing must be done with the gas supply to the heater off. Did the plumber use a sniffer to find any leaks? The gas control valve on the tank might not completely shut off all gas to the heater, leaving the pilot gas flowing, as the old valves often weren't 100% shut off.

    I'd make one change though. I don't see a T&P relief valve on the heater. I'd find a way to install one at the hot outlet, in a "T" as close to the tank as possible.

    Yours, Larry
  • Ironman
    Ironman Member Posts: 7,367
    It looks like there’s a regulator before the gas valve. That also may be leaking.

    If the gas valve is leaking through, it’s very unlikely that you’ll find a replacement, let alone one at a reasonable cost.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • mattmia2
    mattmia2 Member Posts: 9,574
    Is that valve nonstandard or will a modern valve fit the tapping in the tank and you just have to modify the main and pilot burner piping?
  • scubacat
    scubacat Member Posts: 6
    All valves and connections to the tank are original, as when it was originally installed. My father had the house built, and it is now mine. The tank never had a repair issue.
    I'm unsure if there is a more modern, universal, valve. I was hoping that someone in this forum may be familiar with this.
    I will have to contact the plumber and ask him if he soaped all connections leading to the tank. It would be great if correction(s) had to be made there, instead of re-doing all of the mechanics of the valve.
    I believe that this tank also has a standing pilot light (as do my furnace and gas stove). Would it be possible that three standing pilot light appliances (furnace, stove and water tank) could result in a 6 ounce/10 minute test pressure loss?
    A tank of this age would likely have simple mechanics (although proprietary) and perhaps a retrofit of a universal part would work.
    Best to start away from the tank and check connections first. I'd hate to replace the tank without doing my due diligence on it.
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,453
    @scubacat

    You can a least get the plumber back to find the leak maybe it's fixable. But if he has to spend a bunch of time on it it will end up costing half the price of a new water tank
  • I'm surprised that the first solution was to replace all the gas shutoff valves without finding the leak first. That's like replacing a car engine when the dome light doesn't come on.

    Recently, the gas lines on my house were pressure-checked,
    If this was done just by watching the gas meter dials, any standing pilots will show usage; that's no leak.

    Was it the same plumber that replaced your gas cocks that turned your gas off to the water heater, without smelling gas?

    @Larry Weingarten said, "Did the plumber use a sniffer to find any leaks?" Get someone with a sniffer.

    With new gas valves on each appliance, you should be able to isolate individual appliances to narrow down the leak.
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
    Larry Weingartenmattmia2
  • Larry Weingarten
    Larry Weingarten Member Posts: 3,273
    Hi, That is almost certainly an external flue heater, meaning there is no central flue, but the flame wraps around the tank, going between tank and jacket. That's going to make it harder to find a modern control to fit it. I'm still not convinced there is a leak, but rather an open line going to the pilot, which used to be much larger than modern pilots. Methinks the plumber is more comfortable with modern equipment, so is pushing you to replace this heater.

    Yours, Larry
    EBEBRATT-Edmattmia2
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,453
    I agree with @Larry Weingarten The plumber thinks "it's old so it must be junk" I think the opposite . If it was junk it would have been gone a long time ago.

    I would only replace it if part's are not available or the labor cost is too high
    Larry WeingartenSuperTech
  • mattmia2
    mattmia2 Member Posts: 9,574
    I don't think that plumber is the one to fix it.
    SuperTech
  • scubacat
    scubacat Member Posts: 6
    Same. I fear that he has already committed it.....
  • scubacat
    scubacat Member Posts: 6
    edited November 2021

    I'm surprised that the first solution was to replace all the gas shutoff valves without finding the leak first. That's like replacing a car engine when the dome light doesn't come on.

    The gas company, who had shut off the main gas to the house, suggested to have the valves replaced, as they were the old turn-style valves.

    Recently, the gas lines on my house were pressure-checked,
    If this was done just by watching the gas meter dials, any standing pilots will show usage; that's no leak.

    The gas company and the plumber put a pressure gauge on the gas line exiting the meter. After the new shut-offs were installed (4 of them), the plumber tested each one individually. The pressure dropped like a rock when the test was applied to the line going to the water heater. The other gas appliances were fine.

    Was it the same plumber that replaced your gas cocks that turned your gas off to the water heater, without smelling gas?
    The plumber replaced the shut-offs based upon the recommendation of the gas company. No gas was ever smelled. Gas was shut off by the gas company due to their result on the pressure test for all lines (6 ounces lost/10 minutes). I am in Ohio, and it was getting cold - so just wanted to get those valves in order. The gas line to the water tank was capped. The gas company came back out, pressure tested again, and all was good enough to turn the gas back on. I have heat, but no hot water (gas line to tank still capped).


    @Larry Weingarten said, "Did the plumber use a sniffer to find any leaks?" Get someone with a sniffer.

    I do not believe that he used a sniffer; his assessment was made after the pressure dropped on the hot water heater line, using the pressure pump/gauge. I will call and ask him if there were joints soaped or a gas sniffer used.

    With new gas valves on each appliance, you should be able to isolate individual appliances to narrow down the leak.
    Each appliance line was checked individually. All were OK with the exception of the water tank (he says).


    Everyone here has shared some excellent insight with me. I need to get someone to reconnect the gas line to the tank, and to specifically check all connections to the tank (with mind to the pilot). It does appear that the tank control has a specific OFF gas position. This is a challenge to find someone who will check connections and not just condemn the tank because of its age. I'll go back to doing my due diligence on plumbers to find that person.


  • mattmia2
    mattmia2 Member Posts: 9,574
    Was the knob turned to "off" when it was tested?

    You could connect a manometer to the valve and pump it up to its working pressure and look for leaks in that part of the system. Could connect to the regulator and the valve separately. The regulator is a commonly available part if it is leaking there.

    @Larry Weingarten would it be legal to retrofit it with a pilot generator, millivolt combination valve, and aquastat?
  • mattmia2
    mattmia2 Member Posts: 9,574
    Oh, one more thing, i would keep stuff much further away from it in case there is rollout out of the combustion chamber.
  • GW
    GW Member Posts: 4,691
    are you saying they pressurized the valve with air?
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    gary@wilsonph.com
  • scubacat
    scubacat Member Posts: 6
    They disconnected the outgoing gas line from the meter (interior), and applied a pressure test to the gas lines going to the gas appliances.
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,453
    Sounds like they pressure tested the gas lines while they were connected to the appliances.

    Sounds like the appliance gas cocks were open otherwise if they were closed the "leak" would not have shown up.

    Although its' not the technically right thing to do many test the gas lines up to the appliance shut off valves now but only if they are new ball valves.

    In this case with the leak being after the appliance shut off cock it must have been open as they installed new ones
  • I think what Gary means is that you never apply a pressure test to a gas line while the appliances are connected. They did the right thing to disconnect the gas meter, but they should have also disconnected the appliances. It's the way I've done it my entire career as early on, I was told that above a certain pressure, you will blow out the regulator. And I don't even know that a low pressure regulator can hold a pressure test as normal working pressure is 7" wc and a gas pressure test around here is 15 psi which is 420" wc.
    Something is not right there where you are.
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
  • JakeCK
    JakeCK Member Posts: 1,356
    edited November 2021
    GW said:
    are you saying they pressurized the valve with air?
    Didn't a bunch of houses blowup and/or catch fire a few years back because gas mains were over pressurized and blew out regulators?
  • mattmia2
    mattmia2 Member Posts: 9,574
    JakeCK said:


    GW said:

    are you saying they pressurized the valve with air?

    Didn't a bunch of houses blowup and/or catch fire a few years back because gas mains were over pressurized and blew out regulators?

    Yes. It was like 100 psig gas. Probably blew out some valves too.

    Using air to pressure test is a valve within its working limits is fine safety wise, just can't use a combustible gas detector to look for the leak if you find one.
  • GW
    GW Member Posts: 4,691
    Either the story is getting skewed or something is stinky 
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    gary@wilsonph.com