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Troubleshooting Honeywell LG8148G

EthanB
EthanB Member Posts: 4
edited November 2020 in THE MAIN WALL
Contractor but not a plumber here. I've been searching away this afternoon but no dice so hopefully one of you can point me in the right direction. Recently bought this house and the system is on life support, we're waiting for the new system but I'd like to get it comfortable for the next couple months.

I have a Honeywell L8148G aquastat with two zones controlled by Taco valves and a single circulator. They also had a separate 24v transformer. The transformer was dead and one of the Taco's was bad so I grabbed those today but I need to start fresh on wiring as they had kludged it all together. Anyone have a wiring diagram that would be helpful? I've worked on single zone before, and double zone with a transformer but the aquastat is throwing me off. I see the 24v coming from the Tv but nothing from the Z and I don't want to fry the transformer or the aquastat but my understanding is that the L8148 can't power 2 Tacos. Pic of the aquastat if it helps. (guess not, it won't let me upload).

Comments

  • EthanB
    EthanB Member Posts: 4

  • STEVEusaPA
    STEVEusaPA Member Posts: 5,292
    Show us a picture of the zone valves/wiring too.
    steve
  • EthanB
    EthanB Member Posts: 4
    The wiring is disconnected from the aquastat and transformer. They had both taco valves locked open and the Tv to the 1(on the Taco) and the T to the 2 on one valve so it would fire up the boiler and circulator when the thermostat called.

    What's throwing me for a loop is the power coming from the aquastat. If Tv goes to 1, then does Z go to 2 and T to 3?


  • EthanB
    EthanB Member Posts: 4
    That's the type of diagram I'm familiar with, T-T with power from the transformer. I'm not sure what I should be doing differently with the aquastat providing power and, unfortunately, I'm not seeing info from Honeywell for this specific model, they have plenty on the other L8148 model but those show Z supplying the power. I'm getting power from Tv and nothing from T or Z.

    Thanks for the help, by the way!
  • HVACNUT
    HVACNUT Member Posts: 4,184
    EthanB said: I see the 24v coming from the Tv but nothing from the Z and I don't want to fry the transformer or the aquastat but my understanding is that the L8148 can't power 2 Tacos. Pic of the aquastat if it helps. (guess not, it won't let me upload).
    If that's a 40va transformer then it should be able to power those valves fine. No diagram or info on the inside cover?
    There should be 24v between TV and Z at all times.
    T should be connected to terminals 3 (end switch) on the zone valves. Z should connect to terminals 1(Common) on the zone valves. 
    TV connects to R at each thermostat. 
    W from each thermostat goes to terminal 2 on its corresponding zone valve. 
    Taco's ZVC panel, or similar would make it neater simplify everything. 
    EthanB