Buying guides
Already know what you need? Our winter buying guides, compared on maker specs and DOE data.
Black Friday 2026
Amazon prices for 7 ecobee, Nest, Honeywell and Amazon models, tracked into Black Friday.
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Heat pumps
The aux-heat lockout setting that stops backup strips running up the bill.
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Space heaters
Why wattage and a good thermostat matter more than heater type. 4 picks.
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Windows
How much curtains and cellular shades cut heat loss, on DOE figures.
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Drafts
Shrink film and door draft stoppers compared by cost per window.
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Energy monitors
See which circuits drive your bill: Emporia Vue 3, Refoss and more.
See the picks →Also popular: Best smart thermostats · ecobee vs Nest · Thermostats without a C wire · Smart thermostats under $100
Fix it yourself
Our most-read fixes, written from each maker’s own support pages.
Nest
What turned it on and how to get back to your schedule.
Read the fix →Nest
The six features that move the setpoint, and how to stop each.
Read the fix →ecobee
Smart Home & Away, Follow Me, holds and energy events.
Read the fix →ecobee
ecobee’s own fix order, from router reboot to settings.
Read the fix →Honeywell
Default codes by model, and what to do if 1234 fails.
Read the fix →Any brand
Five checks, from the C wire to the furnace door switch.
Read the fix →Compare before you buy
The questions people ask right before they buy, answered spec by spec.
Thermostats
Sensors, heat pump control and price, side by side.
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ecobee
Which ecobee is worth the money.
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Under $100
The three budget picks, by wiring.
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Energy monitors
Local control, clamps and price.
Compare →Heating
Which costs less to stay warm.
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Heating
Which costs less to run where you live.
Compare →Start here
Three paths. One obvious next move depending on whether you want a diagnosis, a DIY walkthrough, or direct help.
Diagnose first
Use the 60-second diagnosis to narrow the problem before you spend money on the wrong fix.
... Start the diagnosis →DIY path
Use the room-by-room checklist if you want to inspect the house yourself and fix obvious waste first.
Open the checklist →Fix it now
Blank screen, “Delayed”, “Wait”, offline or clicking with nothing running: find your fix by symptom.
Find your fix →How we choose
We compare products on the makers’ published specifications, ENERGY STAR certification and DOE and EIA data, and we link every source. We do not test products in-house, and we say so on every guide.
Savings figures on this page are estimates built on published ENERGY STAR, DOE and EIA data — see where they come from. Your result depends on your home, your climate and what you are doing now.