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Eliminating hot water priority

problem is what I had wrote, so say you wake up, take a shower upstairs use hot water, go downstairs right after, the house is 62, turn the heat up, the hot water tank is replenishing, so it takes 30-40 before the heat even turns on, so the house is sitting cold and the burner only fires every 10 minutes after it gets some heat gain.


  • Chris Williams_6
    Chris Williams_6 Member Posts: 12

    Hi I am having a problem on early ams, where we use some hot water and then are done, an go downstairs our house is cold, so we turn the heat on but the hot water amtrol unit is replenishing and has priority so it wont turn the heat on for 20-35 minutes which is a real pain, since our schedules vary a bit a prog thermostat wont help much. I would be fine having everything contend for the heat and at least get some heat knowing it will be a bit slower. Can someone yell me where the wiring is usually for this, is it in the honeywell unit? Thank you
  • Ted_9
    Ted_9 Member Posts: 1,718
    Taco controls?

    If you have Taco controls, inside the control there may be a priority off on switch. otherwise, its wired in the control for priority.


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  • Chris Williams_6
    Chris Williams_6 Member Posts: 12

    I have a L7224 Aquastat and 3 zones, but dont see a taco controlbox anyplace
  • Couderay
    Couderay Member Posts: 314
    why disconnect it??

    Sounds like you need to circulate your hot water be it gravity fed or pumped.Or go to constant circulation on your boiler system. Then again..........
  • Couderay
    Couderay Member Posts: 314
    Just what i wrote

    All I'M saying is that if you circulate your hot water, maybe gravity or use a circulator with a timer going off minutes before you wake your potable hot water will be heated and you could keep your priorty. Maybe get a programable thermostat and kick up the heat before you get up out of bed.Or like you want to do disconnect priorty for the domestic
  • Chris Williams_6
    Chris Williams_6 Member Posts: 12

    Im sorry I guess I dont understand what you are saying. The problem is that I do have a programmable thermostat, and we just got up 2 hrs early today and it stinks if one person goes to a zone 5 minutes after the hot water starts reheating since they wont get heat until its satisfied. I looked and I dont have any other zone control boxes so I am not sure how this gets wired
  • Couderay
    Couderay Member Posts: 314

    Sorry got up to early this morning re edited my last comment.I'm saying to keep your priorty and do something different with your system.If you look in your manuals of your components there should be a way to disconnect your priorty. My system would do the same thing get up take a shower and my indirect took over the boiler.I use no night set back, keep heat at 70 and went to a gravity return on my indirect. This house is very insulated and have had no problems between indirect and heat.I reckon all I'm trying to say is with a few different ways and means I think you can keep your priorty.
  • rucomfy
    rucomfy Member Posts: 43
    Is it possible...

    that there is an issue with the Boiler Mate? Seems like a long time to recover from a normal draw down? Possible heat transfer issues with the inner helix or boiler water temp. Sounds like the control logic is doing exactly what I would expect, priority to the DHW. Disable the priority and return the system to equal status or determine what has changed that has created the issue. To me it sounds like a heat transfer issue....
  • william_5
    william_5 Member Posts: 62


    After looking at the hw page L7224ac or L7224u Idoint see any thing about a priority on this control.un less you have a nother control wired to zr that controls the boiler mate? You said you have 3 zones are they zones vales ? or 3 circulators? the low voltage wire on the amtrol aquastat what control does it go to?

  • D107
    D107 Member Posts: 1,839
    you say 'wake up, take a shower, house is 62'...

    HO here who's worked with the Buderus 2107 control. That control automatically heats up HW half hour before the daytime space heating kicks in. Yours may not do that, but seems like you need to turn space heating on earlier, so that it's not 62 after your shower, but so it's near 68 BEFORE you take your shower AND the rads will be hot --if cast iron. Then if heat goes off for 15-20 minutes to replenish HW after your shower you won't notice it.
  • Chris Williams_6
    Chris Williams_6 Member Posts: 12

    there definitely are no other boxes so maybe its inside the boilermate control box.
  • colbydoglvr_3
    colbydoglvr_3 Member Posts: 12

    call your local heating contractor and he will be able to fix you right up. get rid of the priority as it is just a bad idea in any area that gets cold.(seen more than one frozen solid house do to a dhw priority issue. stay out of your controls if you dont know what you are doing or you might just cost yourself some bigger issues. CALL A PRO!!!
  • J.C.A._3
    J.C.A._3 Member Posts: 2,981

    On the 7224's, the "low limit" is also a "reverse acting" control. The space heating will be off until the low limit is met/satisfied. Only then will the C1 terminal be able to send power to the circulator or relays...if it's wired properly.

    Chris, I'm gonna agree with the programmable thermostat as the "least expensive solution". As stated, get the temperature where you want it BEFORE jumping in the shower. The next step WOULD be to have the Amtrol checked. There is a time/water temperature "suggested recovery" period that will tell you if the coil is/has been compromised.

    A multi relay with priority will just continue to do the same thing if the tank isn't able to recover fast enough.

    Good luck and seek a pro to help you make the best decision. Chris
  • william_5
    william_5 Member Posts: 62
    tripple aquastat

    yes j. c. a. c1 would power the cicr but not the relay that is why the put the zr to power other ralays. now looking over what he read he states that there are no other boxes. So one would have to look that there is one circ and three zone vales witch should tell you that if the boiler mate is calling than so should the other zones. Now if this is true I would want to know what the high limit is set for? sounds like high is set lower than the low limit run cycle with the circ off the burner would come on to main tain heat in the boiler once the high limit was reached you would loose power to b1 the low limit is open no power to c1 as the water heats up from laden heat (peerless wvb boilers turn off at what the aquastat is set for but than the water temp will rise 15 to 20 deg over set point) at that time the low limit switch will close sending power to c1 the circ will start but not the boiler or (b1) high limit is still open. as the temp drops in the boiler from the water returning c1 opens b1 is still open untill water temp drops below fixed set point . b1 now has power c1 is still open water is heating up high limit opens and you start the cycle over agan. this would also account for a short run time on the burner i have seen this time and time agan alot of times it was the home owner lowing the high limit trying to save oil

  • Chris Williams_6
    Chris Williams_6 Member Posts: 12

    I figured out where it is, the pri wiring is within the boilermates control and it locks out the houses heat until its zone is satisfied, though I dont really understand what the point of that is. The tank heats somewhat slowly, so it really is an issue at times, and with the boiler heating say the hot water and another zone or two at the same time, they might heat slower, but at least you get some heat when you want it. The funny thing is they only show wiring for priority wiring, and wiring in a system wheree there isnt even a heating system, if anyone else wants to chime in that woudl b great, I will also call amtrol monday and post what happens. Thank you
  • hr
    hr Member Posts: 6,106
    What size boiler do you

    have to drive the Amtrol? What size piping to it? Either/ or will slow DHW recovery.

    Also check the delta T across the coil when it is calling for DHW. That brand, with a finned copper coil inside, has a habiting of getting coated with hard water deposits and really cutting down on recovery ability. A temperature check of temperature in and temperature out will help determine if you have a constipated coil inside "er.

    hot rod

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  • JC_7
    JC_7 Member Posts: 4

    I just had a 45 gallon Super Stor installed this weekend. I was always told that the indirect water heater should be set as priority, yet my friend who is experienced said that many people are getting away from prioritizing DHW. If there is something wrong with the priority zone, then the other zones may not get heated (which is a problem when living in New England).
  • Todd_24
    Todd_24 Member Posts: 9
    DHW Priority - Options

    If you are using the Taco zone relay with priority, you can order a timer card that simply slips in to the control and will "time out" from DHW priority after approx. twenty minutes. This is an easy but little known feature.
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