pump control

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barnartist

Minister of Fire
I have a 24v thermostat. I want that thermostat to kick on my pump when the room calls for heat.
I cannot connect the 24v thermostat directly to the pump, I must use some type of relay.

I found these two items (attached) in my stash.

Can someone tell me if this will do the job I need, then secondly how to wire it. I hope you can see the terminals and the corresponding number
s.
relay1-jpg.144918
relay2-jpg.144919
relay3-jpg.144920
 
Sure, it's rated for 1/2 HP fan so should be no problem for most any circulator. Coil draw is only 10 VA so you should be able to find a 24 VAC supply somewhere in your system that can stand another small load for activating the coil.
 
Still need wiring help.... hope someone can chime in!

Used to was they covered wiring a relay in 8th grade shop, as if we didn't already know...

Skip the cob job and go with the sound advice you have received and ignored repeatedly in the past:

http://www.supplyhouse.com/Taco-SR501-4-1-Zone-Switching-Relay

It is designed specifically to meet the requirements of the situation you describe, comes with extensive wiring instructions, and, delightfully, adds even more LEDs to your growing constellation; both green and red, just in time for the holidays.
 
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LOL... come on EW... just say what you really think. ;lol
 
For $300 you could come close to setting up the 100% radiant heat to blissfully pump away 100% of the time and vary the water temperature with outdoor reset.
 
The W-R relay you show in your picture will work. See link:

http://www.supplyhouse.com/White-Ro...acts-175-Ohms-DC-Resistance-334-mA-14912000-p

You will connect the 24 Volts AC wire from the thermostat to one of the coil terminals (bottom, not numbered) and the other coil terminal back to the 24VAC supply such that when the thermostat calls for heat, the 24VAC circuit is completed through the relay coil.
The 120 VAC Hot (Black) wire runs from supply(breaker) to either terminal 3 or 6 (the Normally Open Terminals) and the circulator Hot (Black or Brown) wire is connected to either 2 or 5 (Common Terminals). Tie the Neutral wire from supply to the neutral wire on the circulator (White or Blue). Don't forget the ground wires too!
Note that you shouldn't reverse these wires at the relay as this creates a shock hazard - 120 VAC at terminal 1 or 4 when the relay is not energized.

When the thermostat calls for heat the coil will energize, completing the circuit between 2-3 or 5-6 and sending power to the circ.
 
arbutus, is the type of setup you mention and I long for possible with already installed mixing valves? I assume it would not and new mixing valves would need installed that tie into the outdoor reset. Maybe I can cancel my order if I can quickly figure that out.

Medman, thanks for your reply, I should have been more patient and waited for your response. Would it be too much to ask to draw a schematic of the wiring? I would love to save the coin if possible!
 
So I just looked at outdoor reset mixing valves, they are pricey, $375 for the 3/4 sweat. since I have 3 zones, that would really add up. Then I would still need the controls/thermostats.
 
I don't think so barnartist. I have a Taco I series mixing valve with outdoor reset. 1" threaded from Pexsupply. Looks like prices went up significantly in the past year though, because I recall paying about $325.
I assume your three zones all need different water temperatures or could you get by with one water temp?

My constantly pumped zones do not have zone controls or thermostats, other than an on off switch or plug for the pump. Turn it on in the fall and off in the spring.
 
Depends what's on them for heat distribution.

But I thought you only had one zone, with one thermostat, that you wanted to use to turn on one pump? Hence the single relay question?
 
Wire one side of the transformer to the 24V coil of the relay you have there.
Wire the other side of the transformer through the thermostat and then to the other side of the 24V coil on the relay.

That's the low voltage side of things.

Wire the 120V line (hot) from your power source to terminal 1 on the relay.
Bring 120V from terminal 3 of the relay to the pump.

That;s the high voltage.

Those relays make a loud click when they engage. put it somewhere it will not be disturbing.
 
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