Run a Different Circulator When Boiler Reaches High Limit

Hi. I need some advice can this be done ?
I have a TACO 503 running circulator number1,2 and 3 its wired to a Honeywell 7224 aquastat. The 7224 aquastat also is running circulator number 4 this is running heat to the garage. I want to know how do I also run pump 4 when my boiler reaches the high limit( I want to dump heat ) Do I install a L6006 or a L6006 spdt or do I use a R832A with existing 7224 aquastat. Also how do I wire them trying to do it myself what is the best way to go Thanks

L6006 can do 2 things for you, cut out the stoker motor running and initiate the dump.

Do you have a aquastat well for the probe already installed in boiler to add the L6006?

If not, you must use a strap on aquastat.

I always had an aquastat that makes on temp rise and hooked it to the zone control TT terminal for the zone I wanted to dump to. That way if the zone called for heat or the boiler wanted to dump heat that zone got it. Im sure there are many ways to do the same thing but you don't need an extra pump.

waldo

Use the 24 volts off the Taco 503 switching relay. pass one leg thru the contacts of a strap on aquastat that is taped to the supply pipe as close as you can get to the boiler. When this control closes on temperature rise, it will energize a double pole relay in your 503. One side of that relay will cut one leg of the pair of wires running to your boiler control from the isolated end switch. The other side of the relay will parallel the t-stat of the garage circuit. Omni makes a real nice little cube relay that is $8-10 bucks. it has both normally open and normally closed contacts. The aquastat is the expensive part. One pair low voltage wire is all that is needed from the Taco 503 to the aquastat to do the wiring.

Do you really want to dump heat to the garage? I would dump it to the zone that naturally fires most often within the house, or perhaps to the basement, before I would go to the garage with it.

Oh!!!! My bad. Reread the first post. Garage is running off boiler control. Ok. Let's try again. It's as easy as running an aquastat to the ZC contact in your boiler control?

Next question: When does the boiler get too hot? Is it when idling on the timer, or after long heat calls? If you have the triple aquastat set at 160/200, I could see it getting up to 200 (or a little more) when small zones are calling for heat.

There is an outdoor reset module available for the 7224 aquastat.

Scottscoaled wrote:Use the 24 volts off the Taco 503 switching relay. pass one leg thru the contacts of a strap on aquastat that is taped to the supply pipe as close as you can get to the boiler. When this control closes on temperature rise, it will energize a double pole relay in your 503. One side of that relay will cut one leg of the pair of wires running to your boiler control from the isolated end switch. The other side of the relay will parallel the t-stat of the garage circuit. Omni makes a real nice little cube relay that is $8-10 bucks. it has both normally open and normally closed contacts. The aquastat is the expensive part. One pair low voltage wire is all that is needed from the Taco 503 to the aquastat to do the wiring.

even after your edit post
I would still suggest the ice cube relay route and an external aquastat as you describe vs the zc contacts
It will allow greater flexibility and a 4th step in safety control

On second floor I have 125 degree water in floor radiant heat , boiler set at 160-200 also tried 150-190 feed at 3 teeth 3.25 air. On first floor I have concrete slap with radiant heat, mixing valve also set at 125 degrees everything is fine.
Until it gets very cold and the first floor calls for heat, the boiler is always catching up on 3 teeth. . When I set it at 4 teeth 4 air it works great for the first floor running in a concrete slap, now the second floor hits the high limit and because there is only 125 degree going in lines it takes a long time for boiler to cool down. Once the first floor(concrete ) heats up it holds the heat for 6-7 hours. With a dump zone in my garage and with baseboard fin heat it cools boiler down quick.

If you wire two unique line or low voltage signals to the same load they will feed each other unless you interrupt and or isolate each signal with ice cube relays as Scott described!

Sting wrote:If you wire two unique line or low voltage signals to the same load they will feed each other unless you interrupt and or isolate each signal with ice cube relays as Scott described!

You are correct, I don't know what I was thinking when I replied earlier this morning. I removed my suggestion of the L6006 and line voltage from the previous post and quote so others don't get the wrong idea.

Rob R. wrote:

Sting wrote:If you wire two unique line or low voltage signals to the same load they will feed each other unless you interrupt and or isolate each signal with ice cube relays as Scott described!

You are correct, I don't know what I was thinking when I replied earlier this morning. I removed my suggestion of the L6006 and line voltage from the previous post and quote so others don't get the wrong idea.

So I can't wire up a simple dump zone like you said 120 v with a L6006 aqua stat. Because that will conflict with the circulator in the garage that is already wired up to run with TT. I can't have it both ways,. how should I do it will the cube relay does the cube relay have numbers 1 thru 6 on the poles where does the low voltage come from and how do I run 120 v to pump. Sorry this is all new to me, I guess I need a HVAC guy
thanks again

If you are running zone pumps from a zone board, wire an aquastat (closes on temp rise ,strapon or otherwise) using tstat wire to the tt terminals on the zone board for the zone you want to dump to. Do not use the isolated or end switch terminals, but rather the terminals you are hooking your individual t-stats to. when your set point is reached the circ will come on and dump heat till the differential has been reached.

Or get a plumber

Forget the dumb plumber

get an electrician

Sting wrote:Forget the dumb plumber

get an electrician

OK I will forget the dumb plumber. Do you think a smart plumber will do ? or how about a dumb electrician
Thanks everyone for all your help