Supco 90382 General Purpose Fan Relay, 18 A Load Current, 120 V Coil Voltage, Normally Open and Normally Closed Contacts

Relay worked perfectly for Nest Thermostat controlling a gas fireplace. I also had to install a 24VAC transformer. Very simple configuration:1) The N/O switch contact side of the relay is connected across the gas fireplace switch leads.2) Three wire, 18-gauge thermostat cable (red, white, and blue connected to RH, W, and C respectively on the Nest thermostat) was fished through the wall. The Nest was located a few feet from the fireplace about eye-level on the wall. Fishing the wire through the wall was the hardest part of this install.3) Under the fireplace the wire is connected to the secondary 24VAC side of the transformer using the red RH power wire and the blue C common wire.4) The relay coil is connected to the white (W) control wire from of the nest thermostat, with the other side connected to the blue C common wire. In my install, the transformer and relay were tucked underneath the gas fireplace a couple of inches apart.5) Finally, the primary side of the transformer is fitted with a 120VAC cord (only needed to be about 8-inches long in my case) and plugged into 120VAC.6) On my Nest Thermostat, I had to lie to the thermostat and configure it for "electrical heat" rather than "gas furnace" ... I think. I did this and it works. Read it someplace.This is the 4th Nest Thermostat I have in my home but the only one on a gas fireplace, the other three are controlling two other furnaces, one with two zones, and no relay is required for those applications.Shipping was very fast on this product and I have absolutely no complaints. Would buy again... in fact, I'm about to use another of these relays to control my whole-home humidifier... as soon as I can figure out hot to get the additional wire run to the nest. That's another project.

I used your relay for my homemade emergency lighting system and it works perfectly with my LED light and auto charging battery system.

Easy replacement for the fan relay on my furnace that was getting stuck on.

The fan relay in my air handler went out. Being a recently relocated HVAC tech, I couldn't find any parts houses near my new home and I am not currently employed, so I couldn't borrow one from my boss...so I came on Amazon. I was amazed to see this part as prime eligible...it was getting hot and two day shipping was great.This relay works with a majority (not ALL) air handlers w/ electric heat, utilizing a relay instead of a control board. The normally closed contacts are for whats called a "fan-interlock". This is wired to the heat strips so that when they engage, the blower fan engages if the fan relay fails to switch the normally open contacts closed. A big safety factor and very important when buying a replacement fan relay. If the fan fails to engage when the heat strips come on, you have a big fire hazard - granted, most systems are equipped with high-limit switches now-a-days, but its good to be doubly safe.If you are unsure what you need, save yourself from possible property damage or loss of life - call a HVAC tech.

I used this in my heat only 2-wire system to add a "C" wire to power the Nest Thermostat.Although the Nest worked without the "C" wire, it was temperamental, especially when the Nest called for heat often. As the Nest only pulls power from the two wires when furnace is NOT calling for heat, the Nest would be erratic if the heater was on often, and the Nest could not get enough power.This little relay solved the problem. By wiring it in with the 24VAC transformer in the furnace, and sharing one of the leads with the "C" connection in the Nest, my Nest now always has power, even when furnace is calling for heat.It has performed flawlessly all winter. No noticeable noise other than a very slight "click" when it energizes, but this happens at the same time the other furnace relay clicks, so it's barely noticeable.Bottom line... if you need to add a "C" wire to a 2-wire heating system, this works like a charm!

I am using these to use ecobee thermostats with my unconventional zone valves. Since my valves are normally-open, they require power to remain closed and the power needs cut for the valves to open. These relays do the job perfectly, and since my old thermostats used a third wire to perform this function, these relays only require two wires to do the same thing, thus freeing up the third wire for me to use as a common wire to power the thermostats.The only issue I have is that one of the two relays I purchased has failed and doesn't switch reliably. This causes that zone's valve to remain open and the rooms get far warmer than they should. Simply wiggling the wire causes the relay to audibly click and start functioning again. I have a replacement on order, so we'll see how that one fares.

The Supco 90293 SPDT relay has two pair of controlled contactors, i.e., is double-throw. Pin pair 2 & 4 are normally closed; Pin pair 2 & 5 are normally open. (Pins 1 & 3 are the 24V coil contacts.) The coil will run on either 24VAC or 24VDC; I used 24VDC. The relay's coil may buzz if your 24VAC transformer generates "noisy" power; you'll get less buzz with better "cleaner" AC transformers. A 24VDC power-supply/wall-wart won't have any buzzing. I used this relay to run a millivolt gas fireplace valve with a Nest thermostat: the 24V supply operated both the Nest and the relay, while isolating the millivolt gas valve from the 24V required by the Nest.

Relay installed between nest thermostat and gas boiler. After 2 months of use, one morning woke up to find house at 80 degs and still calling for heat with a thermostat setting of 68! Come to find out relay stuck on. I opened relay and contacts were in perfect condition…Is there suppose to be a return spring to push contact open when coil is off? The was none. If coil pulls contact closed, what pushes it away when coil is off. Switching to RIB