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please tell me if this is ok.....bulb placement

i bought an aquastat with an adjustable differential.
snag is it wouldnt fit inside the well of my amtrol.

i zip tied it to the brass pressure releif valve coming out of the top of the amtrol. i plastered it in heat transfer paste, the silver honeywell stuff, taped it over with a complete large roll of electrical insulating tape, then insulated the whole thing heavily.

now i realize the figures on the aquastat dial may be off........but it should work ok right???

p.s. the brass outlet of the tank is immediately above the steel tank, threaded right in to it.


  • phil the limey
    phil the limey Member Posts: 31

    didnt quite understand the reply.....i know theres a language barrier and stuff....but i thought it would have been easier....anyone else?
  • Weezbo
    Weezbo Member Posts: 6,232

    thats my friend Fangs...sounds like the vampire bit you .

    this while it might go over Big on Red and Green show...might go over Big, you really don't want to do that. not even with unlimited Limited edition Red and Green Duct tape.

    that is a piece of what might be considered your Safety net when the boilers rolling ,...the deal that allows people to sleep at night... you want to get the right well and install it into the well. you can use bolt on auxiliary high limits over and above that level of safety...what you are wanting the thing to do is tell you as soon as it can when the temp in the Boiler, rises to a certain temp.and turns the burner OFF.

    knowing that the temp is 320 above the boiler isn't something you will find many people here willing to tell you is a real good situation not even in jest. *~/:)
  • ScottMP
    ScottMP Member Posts: 5,884
    A standard aquastst control

    can be off anywhere from 10 to 20 degrees " when installed properly ". You have installed it where it could be off 50 degrees. Do you really want some one getting 170 degree water in a shower ? Some little girl getting scaulding water while washing her hands ?

    This is a very dangerous install and should be corrected.

    Please do yourself a favour and correct it/


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  • phil the limey
    phil the limey Member Posts: 31

    i may be mcguiver, but i aint stupid. theres an anti scald mixer on the outlet of the tank before any loads. nobody is getting scalded.

    now....how is anything going to get 320 degrees over the temp of the boiler. dont follow you. i might not be a boiler guru, but help me think this through objecively. the bulb is about 18" higher than it should be. it is not contained in its well, but if the temp transfers to it thoroughly, why wont it be ok?
  • ScottMP
    ScottMP Member Posts: 5,884
    scalding can happen

    at 160 if the right situation accours. I'm not sure what you mean by 320.

    That bulb is to far removed from the tank to get a true reading. What about the tank over heating and causing damage ? Want to see what happens to a hot water heater that over heats ? There's a website that will show you.

    These things are not to be fooled with ... for a reason.

    By the way, you've never seen a mixing valve fail ??


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  • Ron Schroeder
    Ron Schroeder Member Posts: 998

    Not mounting the sensing bulb on an indirect is especially bad because the tank can be calling for heat when there is no output flow of DHW so the tank could get very hot before the heat travels up the pipe to the sensing bulb.
  • phil the limey
    phil the limey Member Posts: 31

    maybe i never made it clear, but there is no need for heat to travel up any pipe to reach the bulb. it is in direct metal to metal contact with the brass fitting which is screwed into the top of the tank. hot water touches the fitting on the underside, the bulb touches the fitting on its topside. is is 2" from the hot water. yes the bulb is 18" from the center of the tank where it would normally reside.....it is only however 2 inches from the hot water, touching directly something which i believe accurately transmits the water temp inside. and as far as the scald thing goes, both the scald valve and the aquastat would have to fail at the same time. as is, i have installed and tested the aquastat as described prior, it works perfectly. so if the concern is a failure, what are the real world chances of both failing simultaneously. that risk is how much risk i am taking. if that is a real risk, then i better just disconnect the boiler now and shower cold, in case something bad happens.
    p.s. i have no idea where someone conjured up the 320 degree temp. i didnt come up with that. the boiler is limited to 175.
  • phil the limey
    phil the limey Member Posts: 31

    The same piece of brass will transmit the same amount of heat, every time, every day. If you have surface mounted the bulb directly to the outlet of the tank, with good thermal transfer, the indicated temps on the aquastat may be off, but they will be repeatable, and predictable. You should be able to trial and error the settings until you are happy.
  • At least

    Why not keep the proper Amtrol aquastat wired in series with your rube goldberg arrange so the Amtrol stat has fail-safe authority over the system temperature??? Not having the Amtrol stat sensing the internal temperature where the factory specifies it should be monitored is dangerous.

    Just my opinion as a homeowner.

This discussion has been closed.