The short version: The Filtrete 3M50 (built on Radio Thermostat Company of America hardware and sold under 3M’s Filtrete brand, now under Emerson/Copeland) was one of the earlier touchscreen Wi-Fi thermostats on the market, and it picked up a genuine base of independent reviews from tech bloggers and smart-home hobbyists at the time. Those reviews describe an easy-to-use touchscreen and generally solid Wi-Fi setup, alongside real complaints about the remote server occasionally failing to communicate with the thermostat for extended periods. We found no evidence this specific model is a current, actively sold product — treat it as a legacy device rather than a current-generation smart thermostat, and confirm with any seller whether cloud/app services are still functioning before buying.

Who It’s For

If you’re specifically shopping the 3M50 (rather than a current Filtrete-branded product), this is likely secondhand, clearance, or old retail stock. It was built for basic forced-air heating and cooling with 7-day programmable scheduling and touchscreen Wi-Fi control.

It’s not a good fit for anyone who wants confidence in ongoing manufacturer app/cloud support — given its age, verify the app and remote-access servers are still operational before relying on it as your only thermostat.

Setup & Compatibility

Early reviewers described installation as requiring a 24VAC common wire connected to the thermostat’s “C” terminal for Wi-Fi functionality to work, alongside standard heat/cool terminal wiring. It supports basic single-stage conventional systems; check compatibility carefully if your system uses multi-stage heating/cooling or a heat pump, since this is an older, more limited platform than current thermostats.

App & Ecosystem

At release, reviewers found the touchscreen interface and initial setup notably easy — one independent reviewer wrote he was “shocked how good a job they [did]” on usability. Others reported a real reliability issue: the remote server occasionally became unreachable for hours at a time, meaning remote/app control could drop out even though the thermostat kept running its last schedule locally. Given the product’s age, don’t assume current app functionality without checking directly, since manufacturer support priorities shift over time for legacy hardware.

Price & Value

Filtrete 3M50
Price (USD) ~$80–130 (varies; likely clearance/secondhand pricing if found)
Where sold Home Depot (historically), Amazon.com
Current support status Unconfirmed — verify before buying
Subscription required No

Pros & Cons

Pros:
– Independent reviewers praised the ease of initial touchscreen setup
– Straightforward 7-day scheduling
– No subscription required

Cons:
– Reviewers documented real server/remote-connectivity reliability issues
– Product appears to be a legacy/discontinued item rather than currently manufactured
– Compatibility and ecosystem support are limited relative to current smart thermostats
– App/cloud support status should be verified before purchase

The Recommendation

Only consider the Filtrete 3M50 if you’re specifically looking for a low-cost legacy unit and have confirmed its app/cloud services are still operational — otherwise treat it as end-of-life hardware.

For a current Filtrete-branded or comparably priced Wi-Fi thermostat with active support, Honeywell’s T4 Pro or Emerson’s Sensi Lite are better bets today.

Frequently Asked Questions

Is the Filtrete 3M50 still sold new?
We found no evidence it’s a current, actively sold product; treat any listing as clearance, secondhand, or old stock, and confirm current app/cloud support before buying.

Does the Filtrete 3M50 need a C-wire?
Yes, based on independent installation reviews, a 24VAC common wire to the thermostat’s C terminal is needed for Wi-Fi functionality.

Are there known reliability issues with the 3M50?
Yes. Independent reviewers reported the remote server occasionally became unreachable for extended periods, interrupting app-based remote control even though the thermostat continued running locally.