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Old cxe5 with honeywell 8148a questions

gusthebus Member Posts: 2

I'm not too experienced so help me out if I'm mistaken. My housemates and I were having problems with our crown cxe5. Mainly pilot and circulation. New circulator was first fix. Then the honeywell 8148 to replace whatever historic piece we had before. Then the fan burnt out. Well we have problems with the pilot again now.

Did research, got aquastat and boiler diagrams and variations.

<a href="http://www.crownboiler.com/manuals/content/All_Models/CXE%20Series%20">http://www.crownboiler.com/manuals/content/All_Models/CXE%20Series%20</a>(all%20models).pdf

<a href="http://www.pexuniverse.com/docs/pdf/Honeywell-Aquastat-Relays-L8148.pdf">http://www.pexuniverse.com/docs/pdf/Honeywell-Aquastat-Relays-L8148.pdf</a>

What the pro wired is not with crowns specs and is a combination of two wiring setups for the 8148e, not our model. We have l3 going to a transformer(I think, it says 60 v on it though) then our pressure switch and finally 24gnd on the boiler. The regular 24 has nothing.

It could be a work around I guess, but it still is the same setup as in the cxe manual so why? Also the circ is on the b's and fan on the circulators...

Now we have no ignition and it has that fried component scent. Just wondering if we should just give up on this thing or if all the more recent problems might have to do with the weird wiring? Thanks.


  • Tim McElwain
    Tim McElwain Member Posts: 4,593
    Whoever the pro

    was that wired this I think messed up. I am not quite sure what you have.

    1. What model 8148 do you have?

    2. Is this a standing pilot, thermocouple system?

    3. Is it a spark ignition system?

    4. Is it a powerpile self generating system?

    You said you had circulation and pilot problems, I assume from your posting the circulator was changed and also the 8148relay is that correct?

    What kind of pilot problems are you having as that may have nothing to do with changing the really but is another problem.

    Wiring sounds messed up as "B" terminals do not go to the circulator but to the burner circuit. Circulator should be wired to to "C1 - Hot", "C2 - neutral.

    Get back to us here with actual number of the relay, number on the gas valve.
  • gusthebus
    gusthebus Member Posts: 2

    Sorry it's the crown cxe 5 gas boiler with an automatic spark pilot(two wires run to the second burner and spark on two claw looking things). It's in that first link. The aquastat thing is the model L8148A. The boiler runs our hot water and radiators I'm not sure about the standing pilot or self generating.

    The first problem was lack of heat and replacing circulator fixed it for a month. Then there was no power and this L8148A was put in to replace what i assume was an older aquastat. Since that a few more problems like exhaust fan, random cutting off and such. Now it's just no power to the pilot/burners and it smells like a burnt electronic by the aquastat.

    It's the weekend so I was digging around and found the manuals and examined our actual wiring. Powers fine to aquastat, but a bracket connects L3 and L1 and this L3 goes to a weird box that has a 60v on it then to the vaccum switch then to smart box for burners pilot etc. The manuals show it should be 24v and go to two terms on smart but it only goes to one 24v term on the smart box right now.

    The c's go to the exhaust fan and the b's go to circulator. From all I can find everything is connected wrong except for the thermostat haha.

    I guess I'm thinking it might be worse off from this wire job(like it damaged everything electric it was connected to). Is it possible the electronics are going to just keep failing after this is replaced and wired correctly? I'm sorry about the typing, so cold comp won't turn on so I'm using iPod.
  • Tim McElwain
    Tim McElwain Member Posts: 4,593
    The L8148A has a

    120 volt burner circuit so B! and B2 will be 120 VAC. Can you take some pictures of this setup perhaps?
  • Tim McElwain
    Tim McElwain Member Posts: 4,593
    I looked up

    the manual for your boiler.

    Wired off B1 and B2 should be the Draft Inducer Motor. B1 and B2 also are wired in parallel with the primary of a AT140C transformer. From the transformer terminal B you should pass through a pressure switch, flame roll out safety to 24 V on the S8600 module.BT on the transformer should be wired to 24V Gnd on the S8600 module.

    The circulator should be wired to C1 and C2 on the L8148A

    Here is the operating sequence:

    1.    Thermostat calls for heat, powering the 1 K relay coil and closing contacts 1K1 and 1K2.

    2.    Circulator pump is powered through terminals C1 and C2.


    3.    Induced draft blower and AT140C transformer primary are powered through terminals B1 and B2.

    4.    When blower gets up to speed and blower suction pres­sure reaches pressure switch setpoint, pressure switch contacts close sending 24 volts to S8600 intermittent pilot control from AT140C transformer secondary.

    5.    Pilot gas valve opens and spark initiates to light pilot burner.

    6.    When pilot flame is proven, spark drops out


    7.    Main gas valve opens and pilot burner ignites main burners.

    8.    If boiler water temperature reaches high iimit setpoint. high limit contacts B-A open, cutting power to blower and S8600 intermittent pilot control. Burners extinguish and blower stops. Circulator pump continues to run as long as the thermostat continues to call for heat. When boiler water temperature drops past the high limit setpoint and through the differential, high limit contacts B-R close, repeating steps 3-7.

    9.    If venting system becomes blocked, blower suction pressure will drop below the pressure switch setpoint, opening the pressure switch contacts and cutting power to the S8600 intermittent pilot control. Burners will extinguish, but blower will remain powered as long as the thermostat continues to call for heat. If venting system clears, steps 4-7 will repeat.


    10.    Thermostat is satisfied, ending call for heat. Relay coil 1 K is de-energized, opening 1 K1 and 1 K2 contacts. Burners extinguish. Blower and circulator pump stop.

  • Ironman
    Ironman Member Posts: 7,180
    "Pro or Con"

    Your "Pro" Installed the wrong aquastat. As Tim already pointed out, the L8148a is for a 120v burner - as in oil burner. You had an L848e which is for a 24v burner - as in gas burner. By send 120v to the 24v controls on your boiler, you now have a melt down and that's why you're smelling electronic fricassee.

    It sounds like you're gonna need a real "Pro" to fix this. When it comes to gas, Tim's the best in the business.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • Tim McElwain
    Tim McElwain Member Posts: 4,593
    No Bob the manual actually shows

    an L8148A with B1 B2 powering a combustion air blower 120 VAC and in parallel the primary of a transformer directlyy off B1 and B2. Sort of odd but it is right off the boiler wiring diagram.
  • Ironman
    Ironman Member Posts: 7,180
    I Stand Corrected

    Thanks, Tim.

    I mis-read Gus's post and thought he said that his original control was a L8148E, which would be the norm for a gas boiler.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
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