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losing heat

Jeff_44 Member Posts: 94
Hello -

I installed a water heater in the fall of 2012. All has been well but as of late, the water temp is starting to drop. I've turned the temp on the tank up a little but after a while, the water temp goes back to where it was.

Any thoughts as to why I'm losing water temps?

Thank You,



  • heatpro02920
    heatpro02920 Member Posts: 991
    need a little more info than that

    what kind of tank? Direct fired gas, oil, electric, indirect with an oil boiler, indirect with a mod con, gas tankless, ect?????

    Did you varify this with a thermometer of some sort, or are you just going by feeling? Most of the calls like this are related to mixing valves and or cold water dilution... I can't count the times I went to a customers house and the problem was their shower valve...
  • Jeff_44
    Jeff_44 Member Posts: 94
    edited April 2014

    This is a traditional stand alone, gas fired 40 gallon tank. I have not used a thermometer - but will do so. My assessment is based on the use of both the bath tub and shower. In both cases, they utilize separate hot and cold valves (original to the house - over 70 year-old hardware). When using the shower in the past, I used to add cold water, now I just use the hot water valve. I'll check with thermometer for a more accurate reading.

    Thank You,

  • heatpro02920
    heatpro02920 Member Posts: 991
    Tank is under 2 years old

    Do you have a washing machine, I have seen faulty washer mixing valves dilute hot water, verify that the water leaving your tank is almost the same temp as what comes of of the nearest faucet...

    it can be any of a few problems, 1 is the thermostat on the tank/ gas valve 2 could be gas pressure 3 could be soot build up inhibiting transfer 4 dilution {cold water somehow making its way into DHW lines}...

    If you adjust the tanks tem and the burner kicks on, check the temp and record it, then next time it gets cold you turn it up again and check the temp, if you have to keep turning it up to get the same temps and your incoming water isnt getting colder {that is very unlikely} than there is an issue..
  • Jeff_44
    Jeff_44 Member Posts: 94
    Thanks again

    I'll first need to get a thermometer. Whats the most direct source to measure the water temp? (right off the tank or a nearby faucet in the basement. Yes, we have a washing machine. How can I check to see if it's effecting the water temp? Could I close off the valves that supply the washer? What about soot? Where would this build up? (in the exhaust line into the chimney?) I run a steam boiler for our house heat and it and the hot water tank exhaust in the same chimney. I cleaned out the bottom part of the chimney last fall - There's been no issue with the boiler.

    Thanks for your help on this.
  • heatpro02920
    heatpro02920 Member Posts: 991
    I would check start by

    checking the temp at the close faucet, you can shut the washers feeds off to see if it helps. As far as soot goes it would be in the unit itself, rare with gas fired appliances {even more rare with natural gas vs lp}, but I have seen it, most of the time it is caused by insufficient combustion air, still kind of rare in a water heater.

    Have you flushed the bottom of the tank lately?
  • RobG
    RobG Member Posts: 1,850
    Hot Water

    The easiest test, just turn on a hot water faucet and walk over to the water heater and grab the hot water outlet pipe, if it's hot enough, you'll know it. Another thing to look at is any two handle faucet that may have the handles open (I have seen a hose attached to the laundry tub faucet with a sprayer on it, the faucet handles were left open and the water would travel from the cold into the hot side tempering the hot water. It could however be a bad thermostat in the gas valve.

  • icesailor
    icesailor Member Posts: 7,265
    Loosing heat to cross connections:


    There is absolutely no way that a washing machine valve can cause a cross connection. The hot and cold water seats are separate and can only be crossed if you take a "Wye" hose connection and connect the Wye end to a washing machine valve and the other end to either the hot of cold of the washing machine solenoid valve. If both washing machine hoses ace connected through a washing machine valve (like  Watts #2), they are still physically separated to the solenoid. If one or both solenoids are leaking, the water flows into the machine. Without equal pressure on both sides of the washing machine valve, the water can not cross connect.

    It may have appeared to that it was the problem but you probably solved it somewhere else and didn't know it.

    The only way I have ever seen it and it is often is when the "wye" connector hoses are used on cheap washing machines that get connected with one hose. Like in really cheap apartments.

    It can't be done.
  • heatpro02920
    heatpro02920 Member Posts: 991
    edited April 2014
    Ice I hate to dissagree

    But I was there on this one, lol...

    The valve had 3 solenoids, and one outlet the middle solenoid was stuck open causing the water to mix through that valve.... These are popular now with them fancy machines and the energy star units...

    heres a picture of what one looks like.. the one they pulled out was a little different, but you get the ide, the one I seen had the solenoids in a triangle pattern, I can not remember the brand.. I can not believe you made me look up a picture of a washer valve... I know I don't have the experience you do but I am hoping I know when I fixed something and when I stumbled through it, lol...


    There is another version of washer out there that will do the same thing, it has 3 solenoids on one side and 1 on the other, the cold pipes into the hot and then into another mixer, very weird way to get something done but they design the machines not me...

    http://www.buyspares.co.uk/image/100/5045174321341/0/z/ and the other side is just a single, so they do the mixing with just one outlet..

    I know the old washers and simple standard units may not have this stuff, and they just have a simple on off for each cold and hot, but I can promise you this has happened, I seen it with my own eyes... I wish someone told me about it before I had to figure it out myself....

    thanks for second guessing me again though Ice, I think the first time was the vaughn pros being cement lined? LOL, keeps me on my toes.....
  • SWEI
    SWEI Member Posts: 7,356
    Triple solenoid

    might be what makes the Cold (70) setting work on some of the newer washers?  
  • heatpro02920
    heatpro02920 Member Posts: 991
    May be

    I am not a small appliance repair tech, they called someone in to fix it, but I seen the old part and it had the 3 solenoids, I have heard of others with a similar issue and I have seen the other dobule inlet setup with a triple valve assembly and then a single..

    The washer we have at our house is crazy, Im sure it has a bunch of crazy valves in there, it has a a touch face controller that you can dial a temp range in...
  • icesailor
    icesailor Member Posts: 7,265
    3 Solenoids:

    The three solenoids are so they machines can control warm and hotter water. If a solenoid is leaking bye, it goes into the tub. There are still only two water connections. Two washing machine hoses. The only place there can be a cross over is still through the valve and the pressurized water will go out and fill the tub. Causing an overflow. If the washing machine valve on the wall that the hoses are connected to works, and you feel both hoses are hot, when the machine isn't running, there is something that is not seen.

    If you're looking for a hot water issue like a potential cross connection, turn off the laundry box valve or whatever the hoses are connected to. If it is a Symmons #400, with the horizontal lever on top, they are notorious for the cold not completely closing. But, they are not physically connected through the valve. I don't believe that a washing machine valve that can cross connect like that can get a NSF rating on the valve. It would be an illegal design valve.

    I wasn't saying that you didn't see what you saw, just that you might have misinterpreted what you found. If I found a bad valve, I told the customer to call their appliance repair person. Let them deal with getting a new valve. My plumbing stopped at the valve.
  • heatpro02920
    heatpro02920 Member Posts: 991
    They called their appliance repair guy

    thats exactly what i did Ice, how it was explained to me is one valve turns on hot one valve urns on cold and then one turns on the tub, they mix in the valve housing and if you look at it you can see how it works inside the valve.. I am not an appliance tech, and no very little about them, besides this incident and my own washer I have no idea how they work, I put clothes in and they come out clean....

    I was told that the new washers come with a check valve that screws on the hose inlet before the hose, so it must be a common problem, I mention it because if not for my thermal imager I would have had a hard time finding the issue...

    Just something to look into, I seen it with my own eyes, turn the kitchen faucet on and the hot wter went hot all the way to the washer but came out of the wall behind the washer luke warm, turned off the cold supply to everything but the water heater and it was hot all over so I new it was cold mixing, checked all the shower valves, everything I could thnik of, traced it with the ti cam and watched it happen like a video game, it was like the hot was sucking the cold out of the washer hose.

    The issue was old but when I put the Rinnai unit it the water must have thought it was easier to go through the washer solenoid than the rinnai unit and followed the path of least resistance... I noticed when I took the pre filter out of the loop it got warmer, that little resistance would help but when I shut the washer box off, it was perfect hot water everywhere....

    If you could hold that valve in your hand you can see what I am talking about, not a great design and to me I dont see the point in using another valve to start and stop the tub, but they do, one for cold one for hot and one for the tub-2 water inlets and just one out to the tub...

    I didn't mean to start an appliance debate, just sharing one of my experiences.
  • icesailor
    icesailor Member Posts: 7,265

    " ""I didn't mean to start an appliance debate, just sharing one of my experiences"" "

    Don't look at it that way. No one ever learned anything by keeping quiet and not participating with their experience. That's a really interesting observation you made. That has the same potential of being a design screw up like the GM key switches that turn off the ignition while the car is driving down the road. 

    There is either a design flaw in the water  passages after the solenoids or a restriction in the outlet hose. Up until the last to years or so, all washing machine solenoids had two solenoids and a three position switch on the console of the machine. Hot, "Warm" and cold. For hot, one solenoid opens. for cold, the other one opens. For warm, both open. With the new 3 solenoid valves. and all the in-between settings, one or both hot solenoids must open. But the only way the cold can get to the hot is if there is a restriction in the water going to the tub. If the hot water pressure in the house at the machine is much lower than the cold, the cold will force its way up the hot water hose to the wall valve and into the system. The whole idea is some form of Green Energy savings. That valve must work with Solenoids #1, Hot and #3, being Cold and #2, being cold but as a  restriction in it that always allows hot water to pass through the valve, When it is in the cool mode, the solenoid is closed, but still passing a small amount of hot water. When it wants a hot or hotter/warm water, the #2 solenoid opens fully. They wouldn't need a sensor to mix it, just a script on the module to match the temperature setting.

    You're lucky you found an appliance repair person that knew what they were doing. Although you had already DX'ed the problem. Appliance repair is the worst business to be in with a failure rate up there with restaurants. Unless that's a common problem, and no one is talking about it (like GM key switches), there wouldn't normally be one of those valves inventoried in the truck. So, it is a two trip call. The two service calls and the cost of the new valve is close to the replacement cost of a new machine. When the customer gets the bill, they go ballistic and want to negotiate the price.

    The only way we find out about these Queebs (glitches) is when we talk about them on Forums like these.
  • icesailor
    icesailor Member Posts: 7,265

    "" " I was told that the new washers come with a check valve that screws on the hose inlet before the hose, so it must be a common problem, I mention it because if not for my thermal imager I would have had a hard time finding the issue... "" "

    That's a serious issue and IMO, rates right up there with the GM key switch. Someone seriously F Up designing that valve. Now, the manufacturer of the valve is sending a check valve to correct the problem if someone figures it out. Or, they junk the machine or it wears out. Dole, Eaton or whatever vulture capitalist investment corporation that now owns them, surely has a large team of highly placed and paid lobbyist watching to stop any hint of the public being informed of this serious safety issue.  Ask any of your appliance repair friends about if they know about a cross connection with the new 3 solenoid washing machine valves. I'll bet they don't know. Service managers don't read the service bulletins, they just put them on a wall for the techs to read, and they don't allow "on the clock" time to read them. If there's a problem and the machine is over 5 years old, they try to sell them a new one.

    Its like that Korean car ferry that rolled over and sank. A canoe has more stability than that ferry. The Japanese designed and built it. It is narrow at the bottom and wide and heavy at the top. It must have been one pukey ride in a seaway. In one photo, it had a stabilizer vane that looked like a right whale flipper it was so big. To stop the rolling. The Koreans bought it and added more weight to the top. It rolled 60 degrees within  less than a 1/2 hour. Ever try to walk up a 12 pitch roof without roof brackets? That's 45 degrees. Imagine if the floor was not almost a wall and you could walk on a wall.

    We find 'em, and fix 'em. "THEY" deny there is a problem. They're smart, we're not.

    I know a criminal type who shared with me his words of wisdom to live by.

    Admit NOTHING.


    Demand PROOF.
  • heatpro02920
    heatpro02920 Member Posts: 991
    I don't mind the debate, lol

    I would rather debate something I know about, since knowing that these new washers with 3 and 4 {some have a triple on the hot and then a single on the cold that just feeds to the hots valve assembly, try to figure that one out} solenoids can cause crossover is one of the only things I know about them, lol...

    I have been on many service calls and have a few friends in the business that feel they can call me when ever they have a problem that takes more than 5 minutes to diagnose, so I tend to see A LOT of "different" situations.

    I don't mind it, I like the challenge, and I like to think I am good at trouble shooting because I use what I like to call "Kid Logic", thats when you take something like a banging steam pipe from a clogged return and convert it to something so simple as thinking about it like an old man walking through a rocky tunnel, or thinking about power as a bouncing ball bouncing in and out of each rollout switch, or warm combustion air as a hot air balloon always wanting to rise and being pushed and pulled in the easiest direction but deflating when there is negative pressure...

    I once walked into a basement that a well known local oil company with 15+ techs and 2 service managers had been pulling their hair out trying to figure out why this boiler was sooting up, as a favor to see what I thought could be causing the problem... It was a 3 section gold that would run for 5-8 days and plug rite up... They had done everything, measured combustion air, down fired, put a larger smoke pipe, a draft inducer, and this thing would still clog rite up in a week...

    I asked when it started and no one knew, they had bought the house with a new boiler in it in the summer time and it didnt start sooting up until they used it for heat..

    So I started by, getting everything back to where it should be, I put the correct nozzle back in, set the pump psi, set the combustion, draft was great, I went rite through it... And I take a smoke test- trace to zero, perfect... So what does that tell me, it runs fine while I am watching it, so WHAT CHANGES? I start looking around, basement is as good as clear, some storage in a corner, the laundry is upstairs, nothing to take my combustion air away...

    So I close it up tight, shut the basement door, and take another smoke test again PERFECT....

    Now I take a walk around the house, what is causing this? no cat fur in the burner fan, no loose debris getting sucked in, no centri air door, all the weird stuff I have seen in the past, so I am thinking this is going to be a new one, kind of excited about it to be honest...

    And then I see it...............

    A turbo blower, the type you would use to dry carpet. It was sitting next to a closet door with an extension cord wrapped around it.. I asked what they use that for and the replay was, His wife cooks for her side business from Friday night to Sunday night every week, and she puts that in the window since there is no kitchen exhaust fan, AAH HAA, lets throw it in the window and take a smoke test shall we, what did we find a 4 smoke...

    I read the label and it was something like 2000 cfm, she used it all summer, but didnt plug the boiler because it was only running for dhw, as soon as it got a little cold and ran for heat {probably non stop since she was pumping heated air outside} it sooted up... case closed.. The service manager that was with me, said "you can not use that fan" I said "sure they can, just open this window at the same time and it wont go negative..." But they agreed it was not going to get used in the winter, since this was just a shoulder month, and she wouldnt be blowing out heated air in January...

    Anyway, when it comes to trouble shooting, you need to think of everything you wouldn't think of, and use anyone elses experiences you can...
  • icesailor
    icesailor Member Posts: 7,265
    War Stories:

    We could have a few beers and swap stories.

    You are blessed with situational awareness and the ability to connect things together that most others can't connect. You must be ADD.

    One of my many analogies for people like us. Like, Johnny does OK in school. Never gets 100% on a test but does OK. Never seems to be paying attention in class, always day dreaming about something. The teacher is always trying to trip Johnny up with a question, She never can. One day, while giving a lecture, she noticed that Johnny is particularly distracted. She calls on him suddenly for an answer on the lecture. He blurts out an answer that is about 95% correct. She is outraged that he could give a correct answer, but DEMANDS to know what he was doing or distracted by. Johnny hems and haws. Finally blurting out, "A cockroach climbed out of that radiator pipe and crawled across the floor. It finally climbed into Sara's bag. where it is right now". Sara jumps up screaming and dumps her bag on the floor where the cockroach runs back down the pipe. The class is giddy with glee for the distraction, the teacher is BS at Johnny for disrupting the class and Johnny is sent to the office for detention.

    The question becomes, who has the attention deficit? No one else in the class saw the cockroach but Johnny and he could still answer the question. A true "Multi-tasker".

    Know anyone like that?
  • Jeff_44
    Jeff_44 Member Posts: 94

    How is this done? is there a blow down valve? Do I just shut off the intake and drain the tank? thanks
  • heatpro02920
    heatpro02920 Member Posts: 991

    just open the bottom valve until it flows clean water, some people will add cleaners and vinegar to the tank, then turn the dial way up to boil it and then rinse it with bleach to make a big deal out of cleaning the tank, but once a year it is good to just drain off the bottom until it runs clean, this keeps your valve working {hopefully} and keeps settling sediment from rotting out the bottom of your tank....