Combining Zones with Taco Relay

smithfan

I have a boiler with 3 zones switched by a Taco SR504. I would like to combine two zones into one. Is it possible to remove the thermostat R/W wires from zone 2 on the SR504, then jump out W from zone 1 to W on zone 2.
Essentially causing both zones to call for heat off 1 thermostat?

HVACNUT

Yes, you can do that.
It might not be W to W.
I believe, but not positive, with Taco, you need to jump the right side terminal on zone 1 to the right side terminal on zone 2.
If that doesn't work, do left to left.

Why are you combining zones though? Will the "jumped" zone over, or under heat?

smithfan

HVACNUT said:

Yes, you can do that.

It might not be W to W.

I believe, but not positive, with Taco, you need to jump the right side terminal on zone 1 to the right side terminal on zone 2.

If that doesn't work, do left to left.



Why are you combining zones though? Will the "jumped" zone over, or under heat?

Boiler is a bit over sized for the house, so I'd like to heat the whole upstairs as one to avoid short-cycling. The jumped zone may over heat a bit. The zone 2 is for both upstairs bedrooms. Zone 1 is for the kitchen and dining/livingroom. I'm not really sure how much overheating will be a problem until I try it. With the taco control it's my understanding the R is the 24Volts out and White is the signal wire coming back. And yes, I believe W is the right-side terminal. Just don't want to blow the thing up! So you've seen this done before?

Ironman

Connect "W" from the zone thermostat that you want to control both to "W" on the other zone. Remove the red and white wires going to the t'stat that you want to disable.

HVACNUT

> @smithfan said:
>
>
> With the taco control it's my understanding the R is the 24Volts out and White is the signal wire coming back.
>
> Yes. Switching is done on the power side through the thermostat. You'll get a 24v reading across R and W (TT) from the transformer coil when there's no connected load. But it doesn't change what your doing.
>
>
And yes, I believe W is the right-side terminal. Just don't want to blow the thing up! So you've seen this done before?
>
>
> Ive done it numerous times on a temporary repair basis.

HVACNUT

Update: I just checked my SR506. It's older, and has cube relays, but on mine, the left terminals are the load side of the thermostat circuits.

smithfan

HVACNUT said:

Update: I just checked my SR506. It's older, and has cube relays, but on mine, the left terminals are the load side of the thermostat circuits.

I'll have to double check mine..Now you have me guessing. I just assumed W would be load side. So would I just check each R/W terminal to common to find which one is the line?

HVACNUT

> @smithfan said:
> Update: I just checked my SR506. It's older, and has cube relays, but on mine, the left terminals are the load side of the thermostat circuits.
>
> I'll have to double check mine..Now you have me guessing. I just assumed W would be load side. So would I just check each R/W terminal to common to find which one is the line?
>
>
> Yeah, you can check it. Or you can just jump the left side, if that doesn't work, jump the right. You won't short anything.
Mine is designated TT, not RW.
Like I said, mine is older, so yours is a newer revision.
We don't use Taco where I work, so I don't run into them too often.

Ironman

You're over-thinking this. It doesn't matter whether "w" is on the left or right; it's still the switched terminal and "r" is still the hot side from the transformer. Just connect "w" to "w" and remove the wires going to the stat that will not be used.

If the terminals are labeled "t t", then you'll need to ring them out.

STEVEusaPA

@HVACNUT Just a question, don't care either way. Is there a reason why you don't use the Quote button when replying to a person? It makes it much easier to read than using these '>'

bob_46

STEVEusaPA said:

@HVACNUT Just a question, don't care either way. Is there a reason why you don't use the Quote button when replying to a person? It makes it much easier to read than using these '>'

I'm trying to figure out what the quote button is and how to use it.

bob_46

WOW

JUGHNE

bob said:

WOW

bob said:

STEVEusaPA said:

@HVACNUT Just a question, don't care either way. Is there a reason why you don't use the Quote button when replying to a person? It makes it much easier to read than using these '>'

I'm trying to figure out what the quote button is and how to use it.

Ironman said:

Connect "W" from the zone thermostat that you want to control both to "W" on the other zone. Remove the red and white wires going to the t'stat that you want to disable.

I was wondering also.......so click into the comment bar....go up to some posting and click Quote.....is that right?

HVACNUT

> @STEVEusaPA said:
> @HVACNUT Just a question, don't care either way. Is there a reason why you don't use the Quote button when replying to a person? It makes it much easier to read than using these '>'
I'm using a phone, so it's set up a little different than the main site"quote, unquote".
Sorry for the confusion.

STEVEusaPA

I didn't know it was different. I never posted from my phone.

STEVEusaPA

For you guys playing with Quote, you can also highlight and delete some of it just so you see the relevant part. For example:
This:

Ironman said:

You're over-thinking this. It doesn't matter whether "w" is on the left or right; it's still the switched terminal and "r" is still the hot side from the transformer. Just connect "w" to "w" and remove the wires going to the stat that will not be used.



If the terminals are labeled "t t", then you'll need to ring them out.

Can get edited down to this:

Ironman said:

If the terminals are labeled "t t", then you'll need to ring them out.

smithfan

You guys are awesome and very quotable.