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Added tekmar 256 to utica dv125

dough041
dough041 Member Posts: 29
in Gas Heating
Trying to be brief and am not too well written- I have a 1999 utica dv125 gas fired hot water system. 3 zones controlled by 3 thermostats and 3 taco circ pumps. Also has a honeywell aquastat. Just added a taco sr504 exp 3 zone relay. I believe i wired the tekmar 256 correctly ( xx from relay to tekmar then 5/6 to boiler tt..now when i turn up a thermostat call for heat only the circulating pump for the zone calling turns on but the boiler doesnt fire). When i test the tekmar it does attempt to fire and indicate a boiler demand? Im sure im not explaining it correctly but any help is greatly needed. Someone had said that the gas valve may need to be “ split”...i’ve done diy on the boiler - mostly changing out new items where I just followed what was being replaced. Thanks for bearing with me.

Comments

  • Zman
    Zman Member Posts: 7,611
    The wires from the "TT" on the Taco need to land on 7 and 9 on the Tekmar. You will need apply an external 24 volt power source to 8 and 9 on the Tekmar.

    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • dough041
    dough041 Member Posts: 29
    I really appreciate your comment. What I did was connect the xx
    (end switch on the taco relay) to 7 and 9 on the tekmar. Then the 5/6 on the tekmar to the T/T on the boiler? I only see connections xx ( end switch on the relay) and T/T connection on the boiler...
  • Zman
    Zman Member Posts: 7,611
    It should be working then.
    I assume you have 24 volt power to 8 and 9?
    If you jumper 5 to 6 does it fire? What is the boiler aquastat set too? Are all your sensors connected?
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • dough041
    dough041 Member Posts: 29
    Get up at 4am for work so will try to jumper 5/6 in am and see if it fires or shows boiler demand signal on tekmar...the boiler is downstairs but I think its a honeywell 1080b1512? Sure thats probably not right but i think its 180 top limit and lower is 20 below that?
  • dough041
    dough041 Member Posts: 29
    Yes ...have 24 volt to 8/9 and the sensors on the tekmar seem to be functioning ( shows outdoor temp).
  • Zman
    Zman Member Posts: 7,611
    Jumping from 7 to 9 should make the controller show the burner symbol on the controller. Jumping 5-6 should manually fire the boiler.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • dough041
    dough041 Member Posts: 29
    Seems all I had to do was change one of the dip switches on the taco sr503 exp ( 3 zone relays) to priority and it seems to work now. Not sure why that is? Don’t know if that is the right thing? 
  • dough041
    dough041 Member Posts: 29
    When I switched the dip switch on the taco relay board to priority now it seemed to fire properly? Not sure why although if you see the taco SR503 - exp wiring , it has several ways to wire the circ pumps- primary, zone 1 zone 2 zone 3 ( priority) and zone 3 N/C...i have zone 1, zone 2 and zone 3 ( priority) with the priority dip switch to on? A little lost here... appreciate any help...
  • Zman
    Zman Member Posts: 7,611
    When set to priority, it should be disabling 2 zones when the third is calling. You work normally make a load like DHW the priority over heating zones.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • dough041
    dough041 Member Posts: 29
    Ill try to attach my relay
  • dough041
    dough041 Member Posts: 29
    Taco sr 503 exp
  • dough041
    dough041 Member Posts: 29
    I jumpered the zc/zr, turned the priority and reset dip switches to off and it so far ( knock on wood haha) seems to be functioning. Ive never seen an outdoor reset used, anything specifically I should look out for or do different? Tekmar 256...Thanks for all the help, truly appreciated!
  • Zman
    Zman Member Posts: 7,611
    You should be able to read the target temp and actual temp. The target will vary based on outdoor temp is it operating correctly. Some over/undershoot of the target is normal to avoid short cyclng.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • dough041
    dough041 Member Posts: 29
    How to tell the target temperature? The outside temp is constantly displayed...
  • Zman
    Zman Member Posts: 7,611
    The button on the left changes the menu. The other two scroll through the menu. If I remember correctly, you want to be in the "view" menu and scroll.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • dough041
    dough041 Member Posts: 29
    Thanks, will check. I do most all my own work ( out of economic necessity) but actually enjoy it. The internet and sites like this are so great with people like you helping others. ...

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