Review · Our pick · Smart thermostats
WarmWise 3 review
Controls the furnace with modulation and saved 11 percent on energy in our test.
Tested by Jake MorrisonReviewed by Ryan MitchellIn use October 15, 2025Purchase Bought ourselvesUpdated September 1, 2026Reading time 5 minutes
8.9out of 10
8.9/ 10
Our test scoreWarmWise 3
Savings9.2
Installation8.8
App9.0
Integrations8.4
Check price on AmazonPrices checked September 30, 2026. We may earn a commission. Learn more
6-month price historyLowest: $219
$245
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Controls the furnace with modulation and saved 11 percent on energy in our test.
Pros
+OpenTherm support
+Works with all major smart home platforms
Cons
–Installation requires some handiness
Specifications
Price from$219
Test score8.9 out of 10
Rank in our testOur pick
Tested inThe best smart thermostat
Models compared8
Test period12 weeks
How it compares
| WarmWise 3 | Thermi Go | WarmWise Pro | |
|---|---|---|---|
| Test score | 8.9 | 7.9 | 9.1 |
| Price from | $219 | $119 | $299 |
| Rank | Our pick | Budget pick | Upgrade |
Alternatives
Frequently asked questions
Does a smart thermostat work with every HVAC system?+
Almost all modern systems work with it. Some models need a C-wire for continuous power.
How much do you really save?+
In our test, between 6 and 11 percent on energy compared with a programmable thermostat, depending on how often you’re away.
SourcesHouseholdMe in-house measurements (2026)Manufacturer specifications and manual
Changelog
September 1, 2026Prices checked and review updated.
October 15, 2025Review published.
Tested byJake MorrisonHVAC installer by trade, tests tools and smart devices for the home.
Reviewed byRyan MitchellReviews every buying guide before publication. Former consumer news editor.
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