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24-Volt Transformer

  • Step down transformer
  • Knockout mount
  • For use in 24 Vac control systems
  • See More Details

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Product Overview

This Honeywell NEMA Standard Transformer is a multi-mounting. 24-Volt control circuit step-down transformer designed to power any 24-Volt control system, including thermostats, gas valves and relays. 1 year limited warranty.
  • Override protection provided
  • Color-coded 9 in. lead wires for primary connections
  • Energy limiting, meets NEMA standard DC20-1992
  • Transformer is marked NEMA type D, meets NEC class 2 not wet, class 3 web UL 1585 requirements
  • -20 degrees Fahrenheit to 105 degrees Fahrenheit temperature rating
  • Connections 2 screw terminals can be foot mounted, plate mounted or clamp mounted
  • Voltage: 120 (50/60 Hz)
  • Click here to shop all Honeywell Home thermostats
  • Click here for more information on Electronic Recycling Programs

Specifications

Dimensions

Product Depth (in.)
2.5
Product Height (in.)
3.25
Product Width (in.)
2.25

Details

Brand/Model Compatibility
Works with all applicable brands
HVAC application
All HVAC types
Product Weight (lb.)
2
Returnable
90-Day

Warranty / Certifications

Manufacturer Warranty
1 year limited warranty

Questions & Answers

38Questions14Answers

I installed this to add the C wire for my Nest thermostat however I can't seem to get it to work ...

Asked by Andrew December 27, 2020
0
Answers

How much noise (buzzing) does this transformer make?

Asked by Paul December 16, 2020
2
Answers

You should not hear a buzzing noise.

Can I put a three prong plug on this and just plug it into a outlet?

Asked by Chuck October 19, 2020
2
Answers

It's meant to be installed inside some kind of enclosure but it will work, just make sure you connect a ground wire to it.

Is this transformer safe to use for two 24 volt uv lights are installed on furnace and on 24 hours a day every day.

Asked by Jim September 27, 2020
2
Answers

Without knowing the amperage draw of the UV lights I can't say. As long as you don't exceed 40 VA the transformer should be fine for 24/7 usage.

Is this enough power for a Ring Doorbell 2?

Asked by Jenny April 11, 2020
2
Answers

I am doubtful on a 24v one for I needed a 16v transformer that I bought here on Home Depot.com for my Video doorbell Pro. So I would check on the voltage requirements on your model

Can I power more than 1 thermostat or a thermostat and a Ring doorbell with this transformer?

Asked by Rivrat March 4, 2020
1
Answer

This is a 40 VA transformer and can handle multiple thermostats. It should be able to handle a thermostat and door bell as long as the door bell is rated at 24 volts.

does this transformer use aluminum wiring to connect to the mains and, if "yes", what's the best ...

Asked by willie January 4, 2020
1
Answer

The wiring is not aluminum and copper is always the best choice.

It shows 27.49V when I used a multimeter to test voltage. Can I use this transformer for Nest The...

Asked by Hugh December 28, 2019
1
Answer

Hi Hugh, thanks for your question. The Honeywell Home 24-Volt Transformer can be used to supply 24 VAC to low voltage thermostats when needed. If you have additional concerns, we would recommend checking with Nest as they will know more about their thermostat requirements. Hope this helps!

The transformer I am replacing is a 120 volt in 24 volt out 10 va transformer for a Honeywell who...

Asked by Dwink December 2, 2019
2
Answers

It has more power than you need but will work fine in your application.

Can this be installed on an ungrounded but GFCI protected circuit? It would be used to power a wifi thermostat.

Asked by Chris December 1, 2019
1
Answer

The recommend install for this transformer can be found in the manual. If you need additional assistance, please reach out to our support at 1-800-468-1502.

24-Volt Transformer - page 2

Customer Reviews

  • 4.5
    out of 74 reviews
  • 90% recommend this product
Filter by:
Showing 1-10 of 74 reviews
I bought this to add power for a thermostat and so far it is operating as it should after install...
I bought this to add power for a thermostat and so far it is operating as it should after install. The box mount is very convenient although I wish Home Depot carried the other version I have for my furnace control circuit that has all he terminals in the box so no wires are exposed on the outside.
by fixit
The operation of our boiler zone valves was intermittent in the spring. One day they did not move...
The operation of our boiler zone valves was intermittent in the spring. One day they did not move at all. The zone valves moved OK manually. I finally traced the problem down to a weak 24-Volt transformer. I purchased this Honeywell 24-Volt transformer at Home Depot. They had it readily available at my local store. It was an easy install: Shut off the circuit breaker that powers the boiler. Remove the main safety switch box cover on the boiler. Remove the old transformer. Install the new transformer thru an electrical knockout. The wires were long enough to attach to the electrical feeds to the furnace. Attach the 24-Volt wires on the outside terminals of the transformer. They are safe being not covered. Close everything up and then turn on the breaker. Our boiler zone valves were operating as they should. This problem was fixed with the help of Home Depot.
by Toinvent
2 people found this helpful
I got this transformer for my new Ring camera doorbells which require more juice and it did the t...
I got this transformer for my new Ring camera doorbells which require more juice and it did the trick. The Ring Pro requires a higher voltage transformer and the common 16V (or less) transformers aren’t enough power. As soon as I installed this 24V Honeywell, everything worked like a charm! I have a two family home and 4 doorbells running off of it. Two of them are basic backlit-button doorbells and the other two are both by Ring: Pro and Ring2 (both 1080p). All are hardwired to this single transformer and work well. Most HD stores should carry this 24V model, but it’s not in the usual doorbell section. I found it in the HVAC section since it is also commonly used to power newer Smart thermostats. Took me a few minutes to install it myself. Installed super easy after I found it in the basement. They can be difficult to locate in your home, but usually found by the circuit breaker, in the attic or hiding elsewhere. Had mine for about six months now. Hope this helps.
by PaulN
15 people found this helpful
Works fine
I used this to provide power to my Sensi thermostat. My old (50's) floor furnace does not provide power out, so I needed a 24VAC source. This worked great and was easy to install. You can mount it on the cover of a 4" box, with most of the unit outside the box. The portion of the transformer on the inside of the box is the 120V side, so those wires are protected.
by CarlS
9 people found this helpful
by John
I order this online . I didn’t t now home...
I order this online . I didn’t t now home depot sales this 24 volt transformer, it was the right voltage for my project, and it was shipped the next day
by MARIA
Rating provided by a verified purchaser...
Rating provided by a verified purchaser
by HomeDepotCustomer
Rating provided by a verified purchaser...
Rating provided by a verified purchaser
by HomeDepotCustomer
Make sure it will fit in the area you need to put it. It is a bit bigger than I expected.
Make sure it will fit in the area you need to put it. It is a bit bigger than I expected.
by Allen9720
Rating provided by a verified purchaser...
Rating provided by a verified purchaser
by HomeDepotCustomer
Showing 1-10 of 74 reviews