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L8124C and R89A

Duff
Duff Member Posts: 60
Replaced an L8124C today cause it had no h-Limit. In place are four 89A relays one of which  ties into the TT & CC on the L8124C. This system will only go to high temp when the tied in zone to the L8124 calls for heat! The ZC and ZR terminals were not connected.

My question ..... can these R89A relays make the oil burner run?

I can't find any wiring diagram with the L8124C and the R89A.

My gut feeling is that the relays have to be removed and a Taco switching relay box 505 be installed. Any ideas, thanks in advance, Duff 

Comments

  • Paul Fredricks_3
    Paul Fredricks_3 Member Posts: 1,549
    .

    I think the 89A is the same as the R845A relay. As long as there are two sets of contacts in each relay you should be able to wire them to ZC ZR.
  • Paul Fredricks_3
    Paul Fredricks_3 Member Posts: 1,549
    here

    Here's a wiring diagram:

    https://customer.honeywell.com/resources/techlit/TechLitDocuments/69-0000s/69-2041.pdf

    Looks like the 89A only has one set of contacts, so there's no way to do it without adding isolation relays. In that case you might as well add the 505 panel. Or just leave the aquastats turned up.
  • icesailor
    icesailor Member Posts: 7,265
    ZC/ZR Contacts;

    Power the R89A through the ZC/ZR and the system will work as designed. It is a common problem by electricians that don't understand how to wire heating and cooling controls. If it runs and the water gets hot, it's fine and done.

    The reason for Taco Zone Controllers and any other one (like Argo) was to take the Stupid out of wiring heating equipment.

    You just need to change some wires to make it right. The 89A isn't communicating with the 8124. Establish communication through the ZC/ZR and all will be well.
  • Paul Fredricks_3
    Paul Fredricks_3 Member Posts: 1,549
    ?

    Power the 89A through which terminal, the ZC or the ZR. I assume ZC, but how does that tell the boiler to fire? ZR is usually fed by the second set of contacts on the relay, but I don't think the 89A has a second set of contacts.
  • icesailor
    icesailor Member Posts: 7,265
    ZC/ZR:

    Your post seems to be blocked

    The ZC/ZR, when wired properly, feeds the relay of the 89A. The 89A (should be an 845) powers the relay and the relay will start the circulator. It doesn't close the relay for C-1 on the 8124. but flips the burner to be controlled by the high limit. When the boiler temp. drops below the operating or Lo Limit, it drops out ALL the circulators, the one on C-1 in the 8124 and any being controlled by any 845 until the system temp. goes up over the low limit. In other words, it over rides the operating control.

    Its like the little boy in the tome. "When he was good, he was very very good. And when he was bad, he was awful. That's a mis wired or not wired ZC/ZR .
  • billtwocase
    billtwocase Member Posts: 2,385
    it must have been

    originally maintaining temp, and when a relay pulled in, it would run the circ only, and stay within the low limit. You need 845, or 832 relays, or a taco panel relay to take the place of them all. Is there a circ off the aquastat?
  • icesailor
    icesailor Member Posts: 7,265
    Which makes it:

    Which makes it wired bass ackwards.

    If you use the Taco Zone Control, you still need to use the ZC/ZR terminals if you have a tankless or you want to maintain a warm start boiler. They make dog food if you run them cold start. They make Kibbles and Bits.
  • Duff
    Duff Member Posts: 60
    thanks Paul

    thanks for the download
  • Duff
    Duff Member Posts: 60
    thanks Ice

    I'll rewire and see how it operates. So to make this clear as mud let me see if I got ya....the #1& #2 terminals on the 89A have to be wired to the ZC &ZR?

              thanks for the help,   Duff

     
  • Duff
    Duff Member Posts: 60
    Billtwocase

    I'm gonna try what Ice said to do. I hope then that the control will operate the way it's suppose to. thanks for the help. Duff
  • billtwocase
    billtwocase Member Posts: 2,385
    not just

    Z/R, "T-T" can be used at that point. I would make it a warm start
  • Ron Jr._3
    Ron Jr._3 Member Posts: 603
    ZC / ZR controlling RA89s ?

    Without a separate set of dry contacts in the RA89s , how would you exactly wire in ZC and ZR ?



    Like Paul said , the only thing I can see is using ZC to power the relays . But all that'll do is give the boiler low limit protection . It will not let the individual zones make the boiler run to high limit .



    Unless I'm missing something ......................
  • billtwocase
    billtwocase Member Posts: 2,385
    Hello Ron

    nope, you're not missing anything. Can't use the 89A's here without maintaining temp. They are just a switching relay to power a circ only. 
  • Duff
    Duff Member Posts: 60
    gonna go with the Taco switching relay box

    Been looking at wiring diagrams for both the L8124 & the R89A. Just can't see how the 89's would pull in the burner on a call for heat. The OSTemp is 18 & getting colder so it's time to get THE HEAT ON and stop fooling around.

    Thanks to Bill,Ron,Ice and Paul for your help........stay warm everyone, Duff
  • icesailor
    icesailor Member Posts: 7,265
    I didn't say that:

    I didn't say that. There are specific wiring diagrams that show how to use it. Taco has a very good book for wiring controls. Their ZC501 replaces all the Honeywell R8** series control relays. You need to figure out how to wire it. I can't tell you how because in my experience, there are as many ways to wire boilers as there are opinions, and like that referred to body part, everyone has one.
  • Duff
    Duff Member Posts: 60
    Ok Ice

    Ice, thanks for your help,I'm comfortable with the Taco stuff and thanks for the for the advise,I'm going tonight to brush out the boiler and tune it up and will  upgrade the wiring over the weekend. 
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