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Need help with figuring out wiring from old Honeywell Aquastat to new one

Hello folks,

First time posting here.  Need your help figuring out how the wiring would translate from my old Honeywell Triple Aquastat Relay to my new one.  The one that confuses me is the circled piece that is going from L1 to 3 and then from there it jumps straight from there to the hot water tank.  The new unit I purchased is Honeywell L8124A 1015 model.  Also do I need to worry about ZR and ZC connections on the new control since my old one doesn't even have it.  Thank you.

Parth

Comments

  • rick in Alaska
    rick in Alaska Member Posts: 1,250
    Both wires in the original control actually just go to the same place, because of the jumper. So, on the new control, just take the L1 wire and the water heater wire that is currently on L3, tie them together, and connect them to L1 on the new control.
    You don't need worry about the zr/zc connection unless you are using them, which apparently you are not.
    Rick
    dholakiaparth
  • dholakiaparth
    dholakiaparth Member Posts: 7
    Thank you so much Rick, I was thinking the same thing as well but wanted to confirm. Greatly appreciate it.  
  • HVACNUT
    HVACNUT Member Posts: 4,214
    The old control is an L8148A. A cold start aquastat. Why did you change to a triple? 
    STEVEusaPASuperTech
  • dholakiaparth
    dholakiaparth Member Posts: 7
    Old one has this model number.
  • STEVEusaPA
    STEVEusaPA Member Posts: 5,334
    I think someone put an old (different) cover on your existing aquastat.
    What’s wrong with your existing one?
    steve
    HVACNUT
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 2,422
    The old control is model number L8148 The new control is model number L8124. if you have not already connected the control you can return the control and purchase an electronic control L7248 or L7224 for less money (usually)

    You do not need the L8124 control, however, if you have already connected it to your system, you most likely cant return electrical parts once you opened the box.

    No worries though, You can make the L8124 work just like the original control.

    First, you need to remove the red wire and the white wire from the Low side of the limit control and wire nut them together. this will allow the circulator to operate whenever the thermostat calls for heat.
    Next, remove the blue wire from the low limit. this will make the control only operate the burner on a call for heat.

    Now your L8124 will work like the L8148 that you replaced.

    Edward Young
    Retired HVAC Contractor from So. Jersey Shore.
    Cleaned & services first oil heating system at age 16
  • dholakiaparth
    dholakiaparth Member Posts: 7
    Holy **** guys, you are right.  I feel so dumb now.  Thank you HVACNUT and STEVEusaPA, I would have never known.  So here is the actual one L8148A 1124 and the issue with it is that the pump isn't kicking off.  Now can I use the L8148A 1017 since I can't find L8148A 1124.  Any other ones you guys recommend?  Thanks a lot again. You guys are lifesavers.  Thanks a lot again.


    Parth
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 2,422
    @dholakiaparth, Did you already install the new part? If NO, will you be returning the control? Then purchase Honeywell upgrade L7224U. this is usually less expensive and has several functions that may reduce your operating cost.

    I think @STEVEusaPA has a good question!

    I would ask mechanics that worked for me this question...
    After you change out the expensive or time-consuming part, and it does the same thing, What will you check next?

    Sometimes they would answer something as easy as "Check the Fuse". My response would be. Check that first.

    Shazam it works!

    Now find out why the fuse blew.

    And don't tell me they have a queer electrician that keeps blowing fuses.

    Edward Young
    Retired HVAC Contractor from So. Jersey Shore.
    Cleaned & services first oil heating system at age 16
  • dholakiaparth
    dholakiaparth Member Posts: 7
    Hello @EdTheHeaterMan ,

    Yes I am definitely sending the control back now for sure since nothing has been connected to it yet.  Do I need to do anything special if I buy L7224U (it looks totally different compared to my old one) based on my existing wiring on old Aquastat?  Most of the stuff looks fine except the jumper on L1 to L3 and the wire nut on L2.  Thanks again.  Learning a lot here on this forum.

    Parth
  • HVACNUT
    HVACNUT Member Posts: 4,214
    edited November 2020
    If the boiler doesn't already have a Low Water Cut Off, then also look at the Hydrostat 3250 Plus. You would need to change the Well but that's no biggie. 
    Was the old aquastat bad? What's the reason for the change?
    STEVEusaPA
  • STEVEusaPA
    STEVEusaPA Member Posts: 5,334
    I would just get the Hydrostat like @HVACNUT recommended. Although you can do what @EdTheHeaterMan said, I wouldn't. I'm not comfortable telling anyone to modify a UL approved safety control as now you inherit all liability in case of some failure. Better to just get the right one.
    steve
    EdTheHeaterMan
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 2,422
    @STEVEusaPA and I disagree on some points from time to time. Although he does make very good observations and is very well versed in the trade.

    This is one that we disagree on when it comes to the UL listing. In his response, he advocates changing the control from the original Honeywell analog control to a Digital control from another manufacturer. In the same breath, he warns against changing to a digital control from the same manufacturer.

    In the instructions for the Honeywell L7224U there is a list of controls the digital control replaces. Your existing L8148 control is on that list. UL listing is still in place when repair parts are replaced with approved modern parts. So get the L7224U and you will be just fine.

    Edward Young
    Retired HVAC Contractor from So. Jersey Shore.
    Cleaned & services first oil heating system at age 16
    SuperTech
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 2,422
    edited November 2020
    @HVACNUT has a good point, and I agree with him. However, there is additional work required that would mean draining the boiler to replace the well-adaptor (the part screwed into the boiler that holds the control in place). I'm guessing that you are not interested in making more work to replace this control.

    Stick with the L7224U.

    The wiring will be to the same terminals L1, L2, B1, B2, C1, C2.

    you can eliminate the wire nut on L2 by placing both wires under the same screw. You can do the same on L1 for both of the wires from L1 and L3 from the old control. The terminals are designed for a short amount of insulation stripped off and inserting the wire strait in (with no curve or "wrap around" as was on the old control).

    When you are ready to commission the control it will be configured to maintain boiler temperature as a L8124 control (the wrong one). Go to the setup function as indicated in the instructions on page 5. Then go to "LL_" and reduce the temperature until the display reads "OFF" Now your control is set up like a L8148 (the proper control)

    For more efficient operation go to the next menu item "ASC" this stands for anti-short cycling. Crank that up to the longest time. this will keep the burner off for 5 minutes before restarting after a burner shut down for any reason. (high limit, thermostat calls. water heater call). this way the leftover heat may be able to satisfy the call. This may save you a few percentage points on fuel usage and will not show any noticeable change in comfort.
    Edward Young
    Retired HVAC Contractor from So. Jersey Shore.
    Cleaned & services first oil heating system at age 16
    SuperTech
  • STEVEusaPA
    STEVEusaPA Member Posts: 5,334
    @EdTheHeaterMan I think you either mis-read or didn't understand my previous post.
    My disagreement is in modifying a safety or operating control in the manner you stated. I just wouldn't recommend it. If something bad were to happen, runaway control, failed to turn off the burner on high limit, or even a fire, you do open yourself up to potential liability because you modified the control. This brings you into the legal loop unnecessarily-even if the cause wasn't from the modifications made. Who wants that aggravation-both of time and money. Simple scenario, what if the wire nut comes off of the wires that were cut and twisted together, shorting out the control?
    I recommend the Hydrostat, because in my opinion, it's a better control, offers more options, like circulator hold of, and with a well change, low water cut-off.
    steve
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 2,422
    @STEVEusaPA
    You were referring to the modification of the L8124 to make it operate like an L8148. (that was from an old bulletin by Lathimer in Fuel Oil News)

    The way I read it was that you disagreed with the L7224 as a replacement since your reply came after the OP said he was going to return the L8124

    There you go. Clarification makes us both recommend the same idea. Thanks for the response. Good to know we are on the same wavelength. Maybe a different channel but still in the same frequency range.
    Edward Young
    Retired HVAC Contractor from So. Jersey Shore.
    Cleaned & services first oil heating system at age 16
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 2,422
    edited November 2020
    I have one question about the wire from L3 that goes to the water heater. What kind of water heater do you have? A picture from about 6 ft away (or more) showing both the heater and water heater together would be nice.
    Edward Young
    Retired HVAC Contractor from So. Jersey Shore.
    Cleaned & services first oil heating system at age 16
  • STEVEusaPA
    STEVEusaPA Member Posts: 5,334


    ...the same frequency range.

    "What's the frequency Kenneth?"
    steve
  • dholakiaparth
    dholakiaparth Member Posts: 7
    edited November 2020
    Sorry guys for long wait.  Here are the pics.  Whole thing started because of the ER3 code that was coming so a HVAC person came for diagnostic and mentioned the Aquastat needs to be replaced (quoted quite a bit with labor) we were like no way paying that much.  So upon searching on internet I stumbled upon this forum and here I am.  Thank you all folks for now I just placed order for L8148A1017 since my dad didn't want to mess around with digital controls and wanted something that looks exactly the same as my old L8148A1124.
  • dholakiaparth
    dholakiaparth Member Posts: 7

  • STEVEusaPA
    STEVEusaPA Member Posts: 5,334
    edited November 2020
    Please remove the pricing in your post, not allowed per site rules, despite the fact it borders on criminal.
    Error code 3 doesn’t necessarily mean your aquastat is bad. Maybe your zone valve isn’t opening for the indirect or some other issue.
    Can you elaborate on what is/isn’t going on, what was checked and how, what was determined?
    Also I think you have zone valves and one circulator, is that correct?
    steve
    Erin Holohan Haskell
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 2,422
    ...the same frequency range.
    "What's the frequency Kenneth?"
    Exactly, that’s what I’m talkin’ ‘bout 
    Edward Young
    Retired HVAC Contractor from So. Jersey Shore.
    Cleaned & services first oil heating system at age 16
  • rick in Alaska
    rick in Alaska Member Posts: 1,250
    An error three is an overheat condition, which could be caused by a bad zone valve, or a bad aquastat on the water heater. By experience, and the fact it is wanting to heat up right now, my money is on the aquastat, which is ridiculously expensive. They have improved it about five times since that tank came out, and have not gotten any better, but the price keeps going up.
    Depending on how it is wired, you can change it out to a mechanical control with their retrofit kit. That control is not as cool looking, but is a lot cheaper, and works.
    But first rule out a stuck zone valve.
    Rick
  • HVACNUT
    HVACNUT Member Posts: 4,214
    Why the electronics for an indirect? I removed a faulty 24v powered temp controller on a Vaugn yesterday and installed an L4006A.