Reddit reviews Broan-NuTone C909 Tri-Volt Transformer for Door Chime, 9.96" x 9" x 11.04"
We found 3 Reddit comments about Broan-NuTone C909 Tri-Volt Transformer for Door Chime, 9.96" x 9" x 11.04". Here are the top ones, ranked by their Reddit score.
HIGH-QUALITY TRANSFORMER FOR DOORBELL: 8-volt, 20VA or 16-volt, 20VA transformer for use with multiple door chimes in one homeSAFE AND RELIABLE: cULus Listed for safety, ensuring you have a quality, reliable transformer that will pass inspection and a thermal cut-off switch designed to shut off the door chime system in the event of excessive temperatureDURABLE CONSTRUCTION: Constructed of high-quality materials to ensure lasting useEASY INSTALLATION: Transformer features an easy-to-install lock-mount or wall-mount that reduces installation time by 25%IDEAL SIZE: Transformer measures 9.96" x 9" x 11.04", making it the perfect size for your door chime
I didn’t measure the voltage. I bought this.
https://www.amazon.com/NuTone-C909-Tri-Volt-Transformer-Chime/dp/B001PO7MY2
It’s plugged into the 16v 20va section. That was the set my doorbell transformer was originally plugged into.
I have two Ring Pro video doorbells connected to a mechanical chime. I ran brand new doorbell wire to support this installation. I started by using the 16V 10VA transformer that came with the chime.
That worked successfully for a couple of weeks. But then one of the Ring Pro's started going offline due to low voltage.
To solve this problem, I purchased a multiple voltage transformer that could provide either 8V, 16V, or 24V @ 20VA. I started by configuring the transformer to output 16V. The Ring Pros were happy with this setting (that is to say that they didn't go offline anymore due to low voltage). However, in this configuration, my mechanical chime was vibrating constantly (that is, when I removed the chime's cover, I could see that one of the chime "pistons" was continuously moving up and down).
I then changed the transformer to output 24V, and I'm happy to report that everything is now working perfectly. Ring Pros are happy with the voltage, and the chime does not vibrate.
Problem solved!
This is the transformer I'm using:
https://www.amazon.com/gp/product/B001PO7MY2/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1
Hope this helps.
The other answers here are incomplete. According to the Nest website, you need:
"Nest Hello needs to be powered by wires delivering 16- 24 VAC, and at least 10 VA. There are a few ways to check the voltage:"
You need to check your transformer again and make sure it says it provide at least 10 VA. If it doesn't say, then it may or may not work. I bought one of these: https://www.amazon.com/gp/product/B001PO7MY2/
It has the required voltages (16 and 24) and power output (20 VA). My original transformer was only good for 5 VA.