How to wirelessly connect connector wires from air handler to boiler relay?

tommygags

Hi everyone. Recently discovered (thanks to this forum) that the wire connecting my air handler to my taco relay was broken and was seeing ways around running a new wire. Any wireless solutions that you recommend? Tstat wiring is good, just the RW connecting from inside the air handler to the relay is what I'm trying to fix. 

Edit: I have an air handling unit, with a hydronic heating coil. The fan starts, but the circulation pump for the coil doesn't... This is because of the 2 conductor wires are bad and need to replaced that connect to the boiler relay. The air handler is upstairs and the boiler relay is on the first floor on the other side of the house. 

Boiler relay is a taco 503 


Would this work?

 https://www.supplyhouse.com/iO-HVAC-Controls-IO-WRP-4-Channel-Wireless-Relay-PLUS-Kit?utm_source=google_ad&utm_medium=search_dsa&utm_campaign=Dynamic_Search_Ads&gclid=Cj0KCQiAveebBhD_ARIsAFaAvrHBvvEXKh2OYyA_mh6zAhEhcHLsJif9zjefTEHdA5YFZYk-zAPMq-gaAuE2EALw_wcB

EdTheHeaterMan

So this is hard to fully understand what you are trying to do. What "Relay" are you trying to connect to? Where is this "Relay" in reference to your air handler. Does the "Relay" have a part number or model number or can you take a picture and post it?

Based on your description You may be using the wrong term and the "Relay" is not actually a relay but something else.

1. Where is "relay" located in the building?
2. Where is the Air Handler located in the building?

The device you mentioned appears to be able to connect an outdoor heat pump or condensing unit with an indoor air handler, wirelessly. So the contactor relay on the outdoor unit can receive the signal from the transmitter on the indoor unit to the receiver on the outdoor unit. A 24 VAC transformer will need to be added to the outdoor unit to power the receiver and the contactor relay. Looks like it will work with heat pump wiring also.

tommygags

Thanks, hope this helps:

I have an air handling unit, with a hydronic heating coil. The fan starts, but the circulation pump for the coil doesn't... This is because of the 2 conductor wires(RW) are bad and need to replaced that connect to the boiler relay. The air handler is upstairs and the boiler relay is on the first floor on the other side of the house. 

Boiler relay is a taco 503 

HVACNUT

It's only a 2 wire? There's definitely not more that we're cut back? I see one thermostat wire has a Green being used as a Common. 
No closets that line up to drill some holes and run along an inside corner?
How about popping outside and running a wire like the cable guy?
The wireless transmitter you show switches power. It doesn't have any dry contact terminals that would close R-W on the 503.
Honeywell offers an equipment interface module using their RedLink Gateway. But finding a way to run a new wire or repair the old would be cheaper.

ratio

That wireless module you found (nice find, BTW, I'm putting that in my bag of tricks to try out one day) with the addition of a relay to turn the 24vac output to contact closure. RTBU1C is a part number that should be easily found.

tommygags

HVACNUT said:

It's only a 2 wire? There's definitely not more that we're cut back? I see one thermostat wire has a Green being used as a Common. 
No closets that line up to drill some holes and run along an inside corner?
How about popping outside and running a wire like the cable guy?
The wireless transmitter you show switches power. It doesn't have any dry contact terminals that would close R-W on the 503.
Honeywell offers an equipment interface module using their RedLink Gateway. But finding a way to run a new wire or repair the old would be cheaper.

Thanks for this! I could pretty easily run a wire outside, didn't think of that! 

tommygags

ratio said:

That wireless module you found (nice find, BTW, I'm putting that in my bag of tricks to try out one day) with the addition of a relay to turn the 24vac output to contact closure. RTBU1C is a part number that should be easily found.

Sorry for not fully understanding, but are you saying I can use this device in addition to that relay you mentioned for my issue?

pecmsg

Wrong forum

ratio

tommygags said:

ratio said:

That wireless module you found (nice find, BTW, I'm putting that in my bag of tricks to try out one day) with the addition of a relay to turn the 24vac output to contact closure. RTBU1C is a part number that should be easily found.

Sorry for not fully understanding, but are you saying I can use this device in addition to that relay you mentioned for my issue?The relay you found energizes an output remotely—puts out 24 vac. To energize the pump you've got to connect the R to the W on the zone controller. While it might be possible to power the receiver from the zone controller (which would eliminate the need for the relay), you would be less likely to have trouble by powering it separately, which means you'd need a relay to turn the 24v-out to contact-closure for the zone controller.

EdTheHeaterMan

So inside the air handler there is something that the red and white wire are connected to that turns on the pump. Is that a relay or is it directly from R or Rh on the thermostat and W on the thermostat?

It appears that the wireless device you posted WILL work. You just need to know where to connect it on the air handler and on the Taco 503. Both have transformers that can power the transmitter and receiver. (unless you have decided to run the replacement wire)

tommygags

EdTheHeaterMan said:

So inside the air handler there is something that the red and white wire are connected to that turns on the pump. Is that a relay or is it directly from R or Rh on the thermostat and W on the thermostat? It appears that the wireless device you posted WILL work. You just need to know where to connect it on the air handler and on the Taco 503. Both have transformers that can power the transmitter and receiver. (unless you have decided to run the replacement wire)

Thanks!

Here is a picture of the conductor wire, circled in blue, spliced at the top to the white wires, connected to the black box at the bottom:

EdTheHeaterMan

It appears that the air handler has a heat relay. (The one in the blue circle) If the broken thermostat wire is wire nutted to the white wires, and those white wires go to the relay you circled, then you need to determine which wire from the transformer you can use to operate the transmitter. Is there a wiring diagram of the air handler? It may not have all the relays and time delays that are currently there, but it may have enough to give you a sketch of the best way to use the wireless kit.

EdTheHeaterMan

This is the wiring diagram that I have come up with that will work for your system if you decide to purchase the wireless kit. You will need to add an isolation relay. https://www.supplyhouse.com/Jard-92370-SPDT-24V-Heavy-Duty-Fan-Switching-Relay because the iO- P WR WIRELESS RELAY does not have dry contacts. the output is only 24V output. the Taco SR-503 needs only a dry contact like a thermostat or relay contact. If you feed 24 volts to the zone thermostat R and W terminals, you will burn up the control transformer.

SEE WIRING NOTE BELOW
The relay is all low voltage connections so the relay can be mounted outside the SR-503 next to the iO- P WR WIRELESS RELAY receiver. Use the receiver to operate the 24 volt relay. Use the relay contacts to operate the zone thermostat R and W terminals on the SR-503.

One word of Caution: the 24 volt transformer in the SR-503 may be maxed out since you already have a thermostat using the common from that transformer. You may find that adding the isolation relay and the iO- P WR WIRELESS RELAY along with the thermostat that needs the common wire and the relays in the SR-503 may put too much of a strain on that transformer. You may want to consider also purchasing a more powerful transformer for the SR-503. https://www.supplyhouse.com/Packard-PM12440-Multi-Mount-120V-Primary-24V-Secondary-40VA-Transformer. Have it ready if you find there are problems with all the extra power draw from the added parts.

WIRING NOTE:
I have indicated that wires be connected to the red and yellow wires of the transformers on both the air handler and the Taco SR-503. The wires do no need to be connected at the exact location in the photograph/illustration. You can use a wire nut to connect these wires at the other end of the wire. The location selected for the diagram/photo is only for illustrating the electrical path needed for proper operation

HVACNUT

Awesome explanation and diagram, but one or both of the wires from the N.O. contacts going to R-W on the zone panel is broken. So now what?

tommygags

EdTheHeaterMan said:

This is the wiring diagram that I have come up with that will work for your system if you decide to purchase the wireless kit. You will need to add an isolation relay. https://www.supplyhouse.com/Jard-92370-SPDT-24V-Heavy-Duty-Fan-Switching-Relay because the iO- P WR WIRELESS RELAY does not have dry contacts. the output is only 24V output. the Taco SR-503 needs only a dry contact like a thermostat or relay contact. If you feed 24 volts to the zone thermostat R and W terminals, you will burn up the control transformer.

SEE WIRING NOTE BELOW
The relay is all low voltage connections so the relay can be mounted outside the SR-503 next to the iO- P WR WIRELESS RELAY receiver. Use the receiver to operate the 24 volt relay. Use the relay contacts to operate the zone thermostat R and W terminals on the SR-503.

One word of Caution: the 24 volt transformer in the SR-503 may be maxed out since you already have a thermostat using the common from that transformer. You may find that adding the isolation relay and the iO- P WR WIRELESS RELAY along with the thermostat that needs the common wire and the relays in the SR-503 may put too much of a strain on that transformer. You may want to consider also purchasing a more powerful transformer for the SR-503. https://www.supplyhouse.com/Packard-PM12440-Multi-Mount-120V-Primary-24V-Secondary-40VA-Transformer. Have it ready if you find there are problems with all the extra power draw from the added parts.

WIRING NOTE:
I have indicated that wires be connected to the red and yellow wires of the transformers on both the air handler and the Taco SR-503. The wires do no need to be connected at the exact location in the photograph/illustration. You can use a wire nut to connect these wires at the other end of the wire. The location selected for the diagram/photo is only for illustrating the electrical path needed for proper operation

This is awesome, thank you for taking the time for giving me all the information and providing a diagram! This is exactly what I needed, thank you!