“Our old gas furnace quit on a cold night and they had it running again by morning. Fair pricing and no upsell.”
H
HomeownerSt. Marys, ON
Services
Thermostat Repair, Replacement, and Smart Upgrades Near You
A smart thermostat only pays off if it actually controls your system, and St. Marys Heating & Cooling installs and fixes them in homes across town and the surrounding countryside. Century houses often carry old thermostat wiring that needs sorting before a modern unit will behave. We wire it correctly, pair it to your furnace or heat pump, and keep it simple.
Why Homeowners Call Us
Is your thermostat not holding temperature in an older home?
We repair and replace thermostats across Perth County, including smart models wired to work with your furnace, boiler, or heat pump.
Smart Thermostats Done Right
A thermostat only saves money if it is wired correctly and matched to your system. We install smart and programmable models on furnaces, heat pumps, and boilers common to St. Marys homes.
Diagnosing the Real Problem
Sometimes the thermostat is fine and the furnace sensor or old wiring is the issue. We check the whole control chain so you do not replace a good thermostat for no reason.
Works With Older Wiring
Century homes around St. Marys often have thermostat wiring that predates modern smart units. We sort out the wiring, add a common wire where needed, and make the new thermostat behave.
FAQ
Thermostat Repair & Replacement in St. Marys: Common Questions
How much does thermostat repair or replacement cost?
Repairs usually cost less than a replacement, since most faults are wiring, batteries, or sensors. We quote free, in writing, before any work starts.
How quickly can a thermostat be repaired or replaced?
Same-day service covers most calls. We carry common thermostats and parts on the truck, so a morning diagnosis often becomes an afternoon fix.
Should I repair my thermostat or replace it with a new one?
Compatibility matters as much as condition. Older thermostats cannot manage multi-stage furnaces, heat pump staging, or dehumidification, so an upgrade often improves both control and equipment performance.
Reviews
What St. Marys Homeowners Say
Real feedback from neighbours we've helped stay comfortable year-round.
“Our AC was struggling with the summer humidity. They found a dirty coil, cleaned it, and did not push a new unit.”
R
ResidentEmbro, ON
“The ductwork in our century home had decades of dust. They cleaned the full run and the air feels noticeably cleaner.”
H
HomeownerPerth South, ON
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We Can Help Solve Your Thermostat Repair & Replacement Needs
The wall is waiting. Get a free quote today and enjoy a home that finally holds the temperature you set.