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Tekmar/control question- How to get P1 running w/o boiler?

Bucky_2 Member Posts: 9
Hi all, H/O here. Had a card-carrying steamfitter do all my NBP. I ran tubing and designed the controls. Will document and post pix once all is complete. Anyhow, I'm running a W/M injection panel (Tekmar 361 equiv.) for my radiant zone, with a Tekmar 260 controlling the boiler/reset for other zones, along with a Taco SR504 for zone control.

Anyhow, I think that whenever the radiant zone is pumping, I need the boiler pump (P1)to run, also. However, I run P1 off of the 260. TT from the injection zone (along with all rad and the DHW zone) run into the SR504. TT from the 504 goes to the 260. If any zone calls for heat, the 260 will then start P1 and fire up the boiler.

The rub is, lots of times the 361 doesn't call for boiler heat while running, so P1 remains idle. Tekmar says that whenever this zone is running, P1 must also. So how do I get P1 to activate independently of the 260 calling for heat? Thanks for the help.


  • S Davis
    S Davis Member Posts: 491
    P 1

    You need to fire P-1 with a external relay when there is a call for heat on the 361 for the radiant zones.

    S Davis

    Apex Radiant Heating
  • KCA_2
    KCA_2 Member Posts: 308

    I use a design where the Domestic side arm is used a a buffer. Therefor I have the primary pump running whenever there is a call for heat.

    On the taco zone box,. utilize a end switch to run the primary & secondary,. also tie the primary pump into the boiler relay.

    I'll send you a wiring diagram or explain further if you want

    :-) Ken

    To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"
    :-) Ken
  • Weezbo
    Weezbo Member Posts: 6,232
    Electric is lineal ,one thing follows another sort to speak.

    when you start at point A it then goes to point B so..take a piece of paper and draw a ladder then after each step of the way put and or junctions .there always needs to be a path to ground minimum. by drawing a ladder diagram you can think it through.each step has a choise . if you want the system pump to control the heating controls then wire them that way.if you want the heating controls to control the system pump then wire it that way. if you want the system pump to control the heating controls And Domestic Hot water then wire it that way.a ladder just shows you what happens OR doesnt happen next..it takes me alot of time with things when something is thrown in out of the usual set of events unless i draw a diagram and follow that example to the letter.
  • hydronicsmike
    hydronicsmike Member Posts: 855

    ...The W/M Injection Panel has a Boiler Contact on it, which is a dry contact switch. Use it to switch voltage to the Boiler Demand Terminals on the 260 in parallel to the switched voltage coming from your X-X terminals on the TACO SR504 for the high temp zones. The W/M Panel will close the Boiler Contact once the Mixing Device operates above 30% of it's output ( and will then remain closed intul its mixing output drops below 15% again) and the 260 will receive a Boiler Demand, which then brings on P1.

    As long as the W/M Panel operates its Mixing Device below 30%, The Boiler contacts will not be closed and the 260 will not have a Demand or bring on P1 (unless, of course, there is also a call for heat on the high temp zones at the same time). As long as P1 is not running, there is no boiler heat that can be moved by the Injection Pump on the W/M Panel. So naturally, the W/M Panel will have to increase its Mixing Output to satisfy its MIX Target because it is not getting any heat from the boiler. And it will increase its output above the 30% if it has to and at this point, the boiler contact closes and the 260 receives a demand and then brings on P1.

    So basically, don't worry about wiring the P1 to come on any other way than through the Boiler Demand circuit on the 260 that is energized by the X-X terminals from the Taco SR504 for high temp zones or the Boiler contact from the Weil McLain Injection Mixing Panel.

    Didn't tekmar tell you the same? I remember having a phone call like this post last Friday..........If the Injection does not come to an output above the 30%, we dont need to fire the Boiler or run P1.

    Hope this helps.


  • sebast
    sebast Member Posts: 30
    wood boiler piping

    Looking for a piping diagram on piping and pumping a wood boiler into a gas or oil boiler?
  • Robert O'Connor_3
    Robert O'Connor_3 Member Posts: 272
    ..thanks for the replies....

    ...bricks will be placed in the wall as a small token of my appreciation.

    I appreciate all the input....I'll first address hydronicsmike, because this could make everything else irrelevant.

    The tek 361 data brochure (btw, that wasn't me who called last week) Says on p9 in the section "boiler sensor on the return" that "If this mode of operation is selected, the boiler pump should either operate continuously, or be operated in parallel with the system pump contact". What you're saying about letting the 361 TT leads control the boiler/P1 when mix > 30% is intuitive and makes sense; that's why I wired it that way to begin with. But in troubleshooting another problem I ran across this statement which made me go back and re-evaluate my thinking there. But I like this answer; no re-working of my schematics and wiring. :-) So we either have conflicting info from Tekmar here or an "either will work" situation.

    (Incidentally, the problem I was troubleshooting may have just outed itself. I was only getting .33 gallons/min on two 220 ft. 3/8" zones. But now the 012-F4 System pump on the injection panel is screaming really loud. It may have been faulty from the beginning).
  • hydronicsmike
    hydronicsmike Member Posts: 855
    no problem Bucky...

    ...and you're right. I will work either way. Its just that I dont see the need for the external relay wiring for what its worth. The difference in operation is unnoticable.

    You are always very welcome to call us at tekmar at 250-545-7749. I am at extension 214. The only time we so "No", is when it is immediately followed by the word "problem". ;)

    Enjoy your weekend.

  • Robert O'Connor_3
    Robert O'Connor_3 Member Posts: 272

    Thanks again for the help and offer of phone number.

    As promised, there are now two more bricks in the wall in apppreciation of the help from all you guys.

    Now onto the real problem....which may actually have to do with me properly purging the tubing instead of an equipment problem....(return manifold shows only 4 PSI).....I'll let everyone know how I make out..
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