White-Rodgers 24V Coil Fan Relay, 90-380

Update - December 2022: This relay worked reliably for roughly 3.5 heating seasons. Recently, there were two separate instances where it would audibly click when my thermostat came on but the boiler side wasn’t being connected. I tested the boiler wiring directly and it fired up immediately. Since the relay appeared to be the most likely culprit, I replaced it with a spare one I had which immediately worked as expected. I’m satisfied for how long it lasted. I would recommend buying 2 at a time to just always have a spare if you’re ever using it for something like a Nest. The original seemed to fail when the heat was cycling more than usual as well. Guessing it sped up what was inevitable. Otherwise, my original rating still applies. These are simple and easy to use with a pretty decent lifespan. —————— Original Review - October 2019 This little relay is cheap but quality. I got this to use in tandem with a 24v hardwired transformer to control my millivolt boiler. Since my current system had no C wire and was just the Rh/W wires to turn the heat on, I couldn't just plug in my Nest. After some research, it seemed like the safest way to add a 24v power supply would be to use a transformer and a relay. Some tutorials claim plugging in the two transformer wires into the C and Rc ports on the Nest will get it to work (which it will) but you run the risk of the Nest sending the 24V of power down to your millivolt system which would not be good. To get around that, I wired up my transformer then ran the Rh wire to the thermostat and the W wire from the thermostat to this relay on the control end then back to the transformer to complete the circuit. Then just plugged in the Red and White wires coming from my boiler into the controlled side of the relay. Completely eliminated the possibility of the two different voltages crossing and messing anything up on my ancient heating system. I also ran an additional wire for the C and Rc ports to provide continuous power but that's not necessary in this setup, just peace of mind for me. Now that it's been getting cold, this relay has been tested without a problem. The Nest kicks on to call for heat and the relay gives a reliable click with the heat kicking on immediately. Just keep in mind this is a physical relay so the click is going to pretty audible. If you don't want to hear it, put it somewhere tucked away. If you're not a fan, you can find a solid state relay that should do the same thing.

Used this relay in conjunction with a transformer to power a Nest thermostat that controls a millivolt Vermont Casting propane stove. Works perfectly. The stove wires connect to the load side on the bottom two tangs. The white wire from the thermostat (switched) connects to one side of the power on the relay and a wire from the transformer connects to the other. Then a blue and red wire from the transformer connect to common and R on the nest.

Relay had gone bad on my blower to heat pump. This was half the price of the OEM one. This one works fine and blower works again.

I was replacing my thermostat with a smart thermostat - and this required the use of a "common" connection to provide uninterrupted power to the thermostat. Unfortunately, my boiler only had a 24v AC output specific to the ON/Burn - and once connected, there was no power to the thermostat. The solution was to add a separate 30v thermostat AC transformer - using that for powering the boiler's low-water shut-off sensor and for switching this relay - keeping the boiler's thermostat connection / power control completely separated from the boiler's LV switching. (In the process of doing this - I also found that the low-water sensor was not working and replaced it; This was concerning since the low-water shut-off sensor failed in a "closed" state. ) So far, this seems to be working great.

Works as it should

I hope the picture helps you. I'm adding a photo of the wiring diagram and a quarter for sizing, since the label is not shown on Amazon. The description leaves us to search the web for the actual specs. Good price, form factor, and flexible hook-ups. Performance update: I've use 4 of these for a month and they work fine. I was worried about chatter noise based on another review, but mine are quiet except the click to change pull in the contacts. It's likely the power supply of the other reviewer was underpowered and couldn't hold the contacts in securely. When the contacts are pulled in the unit is a few degrees above ambient - slightly warmer than surrounding areas.

I installed this relay to take care of a problem I had with my thermostat turning heat on on my furnace. I was getting a system protest mode error and a note to install isolation relay. Everything works now that I installed this relay.

Excelente

No issues. Simple replacement or use to augment your HVAC system. This is a quality part, not a cheap knockoff. You don't want to risk anything effing up your HVAC controls because they will fail at the worst possible time, guaranteed.

Works great. I measured the current draw of the coil it is only 320ma. Was worried because using my new furnace to control a humidifier and didn't want to much load. But 320ma is very low. I am turning on a small fan and solenoid of the humidifier with the contacts. Works great and my home is no longer dry.

You cannot go wrong with this relay I got this to set up my inline duct fan to come on automatically with the furnace fan. There are some other more practical and cleaner alternatives out there but you can't beat the price on this

description ordinaire...pas clair

J'ai utilisé ce relai pour remplacer celui de mon control de ma thermopompe qui faisait un bruit en tout temps. Ce relai sert à faire partir le ventilateur de la fournaise, aussitôt installé, fini le bruit!