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Where did my hot shower go?

Hello!

We have a Weil McLain GO4 tankless system.

Our hot water is no longer piping hot in the shower and tub and it comes and goes during the shower...about every 3-5 minutes there is a patch of cold for equal time. It seems to get much worse when the temp drops outside. We live on an island so it is hard to find someone knowledgeable about the system...so we are trying to trouble shoot!

We have had the system for about 12-13 years.

Thanks!!!

Erin

Comments

  • Gordy
    Gordy Member Posts: 9,514
    edited December 2016
    Sounds like the tankless coil is scaled, and needs cleaned Erin. Is the heating working fine?

    Is the domestic water pressure on the hot side the same as the cold, or is the hot side notably less?
    SWEI
  • HotShowerPlease
    HotShowerPlease Member Posts: 8
    Hello!

    The pressure on the hot side is way less than the cold. And yes the heating is working fine...forces hot water into radiators.

    We have someone coming to clean it this week. Could that really affect it this much?
  • SWEI
    SWEI Member Posts: 7,356
    It sure could. How hard is your water?
  • Gordy
    Gordy Member Posts: 9,514
    edited December 2016
    Yes this would effect hot water production, and decrease water pressure on the hot side domestic due to the scale in the coil decreasing the piping diameter. It sound like the coil is scaled.

    With the age of the boiler, and your water hardness do you condition the domestic water?

    Do you know the hardness of your water?
  • Gordy
    Gordy Member Posts: 9,514
    edited December 2016
    Be aware also that who ever is coming to clean the coil that acid cleaning will etch the piping surface making it rougher. This will lead to more frequent cleanings in the future due to scale being able to build more easily on the rougher piping surface.

    It just depends on how fouled your coil is as to how aggressive the cleaning needs to be.
  • ChrisJ
    ChrisJ Member Posts: 11,974
    There's also a chance, if it has one, that the mixing valve is bad as well.

    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Gordy
    Gordy Member Posts: 9,514
    Yes that is also true if there is one. Erin do you have one? If so have the person cleaning the coil verify it is not fouled also.
  • HotShowerPlease
    HotShowerPlease Member Posts: 8
    Thanks! Yes we have hard water but I'm not sure how hard. Is the mixing valve a difficult thing to check?
  • HotShowerPlease
    HotShowerPlease Member Posts: 8
    Ok thank you guys!!! I will report back on Thursday if my showers are steamy again.
  • Robert O'Brien
    Robert O'Brien Member Posts: 3,385
    Maintaining 500 lbs of cast iron and 15 gallons of boiler water at 180* 24/7/365 is a very inefficient way to produce DHW
    To learn more about this professional, click here to visit their ad in Find A Contractor.
  • ChrisJ
    ChrisJ Member Posts: 11,974

    Maintaining 500 lbs of cast iron and 15 gallons of boiler water at 180* 24/7/365 is a very inefficient way to produce DHW

    Then why do so many on here recommend an indirect?
    Basically the same principle no? Still have the boiler cooking away the entire time.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • kcopp
    kcopp Member Posts: 3,820
    ChrisJ said:

    Maintaining 500 lbs of cast iron and 15 gallons of boiler water at 180* 24/7/365 is a very inefficient way to produce DHW

    Then why do so many on here recommend an indirect?
    Basically the same principle no? Still have the boiler cooking away the entire time.
    Key word... Maintaining. The tankless coil and the boiler has to stay hot 24/7/365.
    An Indirect heats up and the boiler cools down. No flue, less stand by losses on an indirect.

    Are there better boiler than others to do this sure.
    That and I am not a fan of having a piece of heating equipment sitting idle all spring/ summer.
    ChrisJZman
  • JUGHNE
    JUGHNE Member Posts: 8,949
    A Mod Con would only cook water on demand from the indirect WH. And with dedicated controls ramp up to 180 to get the job done pretty fast.
    ChrisJ
  • STEVEusaPA
    STEVEusaPA Member Posts: 5,313
    ChrisJ said:

    Maintaining 500 lbs of cast iron and 15 gallons of boiler water at 180* 24/7/365 is a very inefficient way to produce DHW

    Then why do so many on here recommend an indirect?
    Basically the same principle no? Still have the boiler cooking away the entire time.
    I don't think it's the same principal. For one, the boiler doesn't maintain the 160-180 degree water temperature, and transitions more into a warm start boiler, only running when needed.
    With more storage you get a longer run cycle to recharge the indirect, and usually never run out of hot water.
    You also avoid short cycling as mentioned above, and the boiler doesn't fire practically every time someone turns on the hot water faucet.
    I do agree they are in common use. Usually because they are being replaced with practically the same boiler, and people usually won't pay the added expense for an indirect and it's associated piping/components.
    My boiler when not needed for heat, probably only drops down to about 110 degrees, and will fire about 3 10 minute cycles to recharge the indirect, for regular use and maybe one or 2 times more for washing clothes (multiple loads). I almost never hear the boiler fire for running the dishwasher.
    In my case I think a .65 nozzle X 30 minutes a day (+-) is way cheaper than an electric water heater maintaining temperature, and cheaper and better for the boiler than a tankless firing multiple times per day for short cycles.
    I almost never hear the boiler fire for running the dishwasher.
    steve
  • ChrisJ
    ChrisJ Member Posts: 11,974
    Still a shame boiler manufactures can't do better than 1/2" fiberglass.

    That's the main problem in my opinion. Throw 2" or 3" fiberglass on it and your losses will plummet. A damper kills most flue losses at least on atmospheric appliances.


    The insulation is a problem whether you use the boiler for a tankless coil, an indirect or just for heat. I hate the amount of heat my boiler losses into the basement. This was most of the reason I dropped a tankless coil and did a stand alone power vented tank heater.




    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
    kcopp
  • ChrisJ
    ChrisJ Member Posts: 11,974
    JUGHNE said:

    A Mod Con would only cook water on demand from the indirect WH. And with dedicated controls ramp up to 180 to get the job done pretty fast.

    Sorry, I couldn't resist. :)



    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Gordy
    Gordy Member Posts: 9,514
    edited December 2016
    I think Erin has a problem that she was looking for possible causes.

    She lives remote. So oil, and or propane may be her only option.
    13 years on a ci boiler is not long. As is 13 years on a tankless coil is not bad if this is her first issue.

    An indirect would save her money in fuel if the budget allows, or as an option if the tankless coil ever goes down the tubes.

    @ChrisJ your meme could not be farther from the truth. Mod/cons can make 190 water no problem. Sufficient for anything other than steam. Also you don't need a hand truck to bring it to the basement in pieces.........
    Mark Eatherton
  • HotShowerPlease
    HotShowerPlease Member Posts: 8
    Ok so someone is here to "service" it now which I guess does not mean to descale the coil. He says he has only ever done that once in 12 years. He is almost refusing to do it saying it will take 5 hours and be super expensive and I should just get a tank. Is descaling really difficult? We replaced the could 3 years ago and it has never been touched since then.
  • ChrisJ
    ChrisJ Member Posts: 11,974
    edited December 2016
    What is he going to do to it.
    Look at it and pray? He came to service it, but he doesn't want to service it. I'm confused. Why is he there?


    My understanding is you pour an acid solution into it, wait a bit and then flush it out.



    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • HotShowerPlease
    HotShowerPlease Member Posts: 8
    He says servicing it is just cleaning out the soot and whatever inside...not the coil. I said ok can u descale the coil and he said I was throwing good money after bad and should just get a tank. But he didn't look at the coil.

    Did I mention I'm on an island? Not a lot of choice. Can a cute housewife descale it herself?
  • Gordy
    Gordy Member Posts: 9,514
    Sooo this guy shows up cleans boiler, and still same performance?????
  • ChrisJ
    ChrisJ Member Posts: 11,974

    He says servicing it is just cleaning out the soot and whatever inside...not the coil. I said ok can u descale the coil and he said I was throwing good money after bad and should just get a tank. But he didn't look at the coil.



    Did I mention I'm on an island? Not a lot of choice. Can a cute housewife descale it herself?

    Sorry, I couldn't help but think of this.





    Can you give us some pictures of the boiler, and the coil and piping around it? It's not too bad if it's plumbed correctly with service ports to connect hoses to.



    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • ChrisJ
    ChrisJ Member Posts: 11,974
    Gordy said:

    Sooo this guy shows up cleans boiler, and still same performance?????

    He allegedly cleaned the boiler, not the tankless coil.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Gordy
    Gordy Member Posts: 9,514
    I know. Soooo my question remains.
  • Gordy
    Gordy Member Posts: 9,514
    Nice schematic however if Erin does not have the service valves that makes thing a bit more difficult.
  • HotShowerPlease
    HotShowerPlease Member Posts: 8
    He's still here cleaning the inside.
  • Gordy
    Gordy Member Posts: 9,514
    Let us know if he cleans coil. Sounds like he is trying to sell the indirect.
  • Abracadabra
    Abracadabra Member Posts: 1,948
    edited December 2016

    He's still here cleaning the inside.

    He needs to descale or you're not getting anywhere..
    if it were me i'd send him packing

    He's just going to clean the boiler/soot/etc then he'll show you that you still have the same problem.. then tell you to buy a new one
  • ChrisJ
    ChrisJ Member Posts: 11,974
    Gordy said:

    Nice schematic however if Erin does not have the service valves that makes thing a bit more difficult.

    Ahem,

    "Can you give us some pictures of the boiler, and the coil and piping around it? It's not too bad if it's plumbed correctly with service ports to connect hoses to."
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • HotShowerPlease
    HotShowerPlease Member Posts: 8
    It was the mixing valve...which was the other thing you guys said to check. Water was 180 coming out of the coil but only 100 going up the pipe. 15 minute fix and I have pressure and amazing hot water. Thank you sooooo much. Walter wouldn't have checked it if I wasn't pushing with your information. Merry Xmas!!!
    ChrisJkcopp
  • Gordy
    Gordy Member Posts: 9,514
    Welcome merry xmas