Taco Controller

Stephen B. Eller

I just installed a Taco 4 zone switching relay to control my baseboard hot water circulator pumps. I now realize that my thermostats are supply 24 VAC when they are calling for heat. The Taco controller is also supplying 24 VAC to the thermostat connections. Can the Taco controller be set to work my thermostats. Changing them would be difficult as the heat is a second stage to my geothermal heat system.

Empire_2

Stephan

What are u using for zones,...valves or pumps? Generally the t stat connection on your Taco controller is nothing more that a set of NO contacts waiting for the stat to close. What you can do depending on what you have is energise a separate relay off of each t-stat to utilize a set of contacts to separate the stat from the Taco controller. Are you using WR 3 wire zone valves? A little more info would clear things up.

Mike T.

Stephen B. Eller

Taco Controller

I'm using 120 volt pumps. The Taco controller is putting 24 across the TT contacts, and as you say, waiting for the stat to close. However, my stats are set up to supply 24 VAC themselves, not just close a contact.

I could add a relay for each stat, but I was hoping I could just change a controller setting and be done.

Empire_2

Stephen

I think in this case you are stuck on adding the separate relay for the TT terminal on the Taco. Since your t-stat is 1st stage Geo and 2nd stg is also powered with another t-former, you have no choice,....WAITE A MINUTE......I was thinking,...why cant we phaze the 2 t-formers together and then I think that would work. You would need an additional 3 wires total going up to the stat. RH,W2 which you have already and Comm.

I'll let someone else chime in, but I think that would work.

Mike T. That's if you have the extra wires..........

carol_3

I'm having trouble understanding how the thermostat is providing power. A thermostat is just a switch . . . What kind of stats are these?

Empire_2

Carol

I think his geothermal is powering the stat through the air handler which is first stage of his system. Second stage is the boiler loop heat. Don't quote me but that's what I am thinking.

Mike T.

Joe Mattiello

If you're using a t87 with sub-base for heating and cooling, I believe there is a jumper on the sub-base that needs to be removed so the two transformers do not butt heads.

carol_3

That's true on a lot of stats. If there's a jumper between R and Rc, and there are separate transformers for heating and cooling, remove the jumper.

Stephen B. Eller

Taco Controller

There is a jumper between RC and RH on each of the 4 stats. I can remove it, but will that cause a problem since the boiler is second stage heat to my heat pump?

Here's the stat wiring. Red and White end up at the Taco controller (with 24 Volts when calling for second stage heat).

RC - Jumper to RH

RH - Red

R.V. Cool (O) - Orange

G - Green

Hum/W1 - White

Deh/Y1 - Yellow

W2 - None

Y2 - None

Empire_2

Stephen...

Add the relay. I think that would solve the problen and will not take much time. Also, you should be using w2 for your second stage or until and if the Goe cuts out.

Mike T.

Stephen B. Eller

Okay thanks. Can I ask why W2 would work better?

Also, can you tell me where I can order they relays? I've spend time seaching online but I haven't found what I need. I'm looking for 24 volt AC to 24 volt AC, single pole single throw, normally open, 1 amp???

Empire_2

Stephen

Any wholesaler HVAC will have a single pole/single throw relay. If you Goe is 1st stage, ( maybe I am confused) what is your supplemental heat or 2nd stage? OR do you want to bring on everything at one time, meaning Geo and boiler pumps...? In your first post you said your Goe is first stage and second stage was the pumps, boiler heat...????

Mike T. PS relats cost about $6-8.00 each.

Stephen B. Eller

The geo is 1st stage and the bioler is 2nd stage heat. That part works fine.

I would think it would be easy to find the correct relay online, but I've had no luck yet.

Stephen B. Eller

I've found what I need. Many thanks!!!!

Empire_2

Very welcome Stephen:

Usually in most areas, the wholesaler has a wide array of relays to suit many needs. Your system only needs to close a set of contacts with minimul load say .6 amps if that. I am glad this is resolved and maybe you can help me out in the future if I need it....;-)

Mike T. GO Bills/Sabres...;-)