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🔥 Upgrade your HVAC game with Emerson’s rock-solid relay!
The Emerson 90-380 Fan Relay features a 24V coil and a heavy-duty 90-amp silver contact rating, designed for reliable, quiet operation in HVAC systems. Its fireproof brick-red casing provides enhanced safety, while its universal mounting and compatibility with modern thermostats like Nest make it an essential upgrade for millennial professionals seeking dependable climate control solutions.
| ASIN | B000LDCPQS |
| Best Sellers Rank | #283,362 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #179 in Solid State Relays |
| Brand Name | White-Rodgers |
| Coil Voltage | 24 Volts |
| Connector Type | Connector_type |
| Contact Current Rating | 90 Amps |
| Contact Material | Silver |
| Contact Type | Switching |
| Current Rating | 90 Amps |
| Customer Reviews | 4.6 4.6 out of 5 stars (1,397) |
| Global Trade Identification Number | 00786710028366 |
| Included Components | White Rodgers 90-380 Fan Relay 24 Volt Coil |
| Item Type Name | White Rodgers 90-380 Fan Relay 24 Volt Coil |
| Item Weight | 0.1 Pounds |
| Manufacturer | White Rodgers |
| Maximum Switching Voltage | 24 Volts |
| Minimum Switching Voltage | 24 Volts (DC) |
| Model | 90-380 |
| Mounting Type | Wall Mount |
| Number of Terminals | 1 |
| Operation Mode | operation |
| Part Number | 90-380 |
| Specification Met | UL |
| UPC | 095801794906 786710028366 |
| Unit Count | 1.0 Count |
| Wattage | 2.16 watts |
C**.
Easy way to make Nest Thermostat work with a millivolt system!
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.
F**B
Solid alternative to the OEM relay at half price
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.
M**N
Great for connecting a smart thermostat to a millivolt stove
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.
A**X
Perfect for my Ecobee thermostat!
Perfect match for my new Ecobee smart thermostat. My boiler does not have a transformer or modern R/W/C etc connections, it has T/T connections compatible with the old mercury thermostats. Pair this with a 24v transformer and my new school thermostat works great!
J**A
Feels cheap, but works fine so far.
This one seems a lot more cheaply made than the original to me. However, it's kind of hard to go wrong with a relay. My guess is it will have a lesser lifetime. However, finding an original model that exactly matches these specifications is rather hard and it's not unusual for them to be $50+ for the same basic specifications (which is a total ripoff based solely on the fact that it's a "specialist" product and thus they can get away with it.) My old one was almost completely stuck (even tapping required several tries to unstick the old one) though and this was a bit of an emergency purchase, so I'd say that in the time I've used it so far I've more than gotten the cost out of it.
M**O
Excelente
Excelente
R**D
Worked with my thermostat
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.
P**S
Easy install
Not sure about it ac still did not work, but not sure if it thermosta or low of freon
K**C
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.
S**N
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.
J**E
Pour thermostat de fournaise
S**E
description ordinaire...pas clair
B**K
Did its job, connecting Nest thermostat to my Lennox furnace to make it run properly, GOOGLE and LENNOX should get together to correct this “PROBLEM”, and quit BANGING HEADS
Trustpilot
4 days ago
1 month ago