Room is cold, thermostat says it is warm
Placement or a failed sensor. A control mounted on an exterior wall, in sun or next to a heat source is reading its own microclimate rather than the room.
Heating & Cooling10,702 businesses licensed for it
Thermostat repair and replacement
A surprising share of no-heat and no-cooling calls end at the thermostat, and it is the cheapest possible outcome. Work covers dead or blank displays, a control reading a temperature the room is not at, schedules and lockouts nobody in the building remembers setting, staged and heat-pump wiring, and replacing a failed control with one that matches the equipment. It is worth ruling out before anyone climbs on a roof.
Enter your ZIP to see the businesses listed for this trade nearest to your site, with their phone numbers.
- Free to searchno account, nothing to submit
- Public registersevery listing names its source
- License numberswhere the state publishes one
- Directyou call the business yourself
- Our estimate
- $150-$950
- Time on site
- 0.75-3 hrs
- Fault patterns covered
- 2
- Licensed for this trade itself
- 10,702
What thermostat repair and replacement costs
Most of these jobs land near $320. The full spread runs $150 to $950, and the gap between those two ends is diagnosis against replacement rather than one business being dearer than another.
What moves it: how much of the job is parts, whether the fault is found in the first hour or the third, access to the equipment, and the hour of the day you call. We never speak to the businesses listed here, so there is no rate card behind any of this. It is our own band for the category, and there is no regional index: the figure does not change with your metro.
| How soon you need it | Typical | Range |
|---|---|---|
| Scheduled visitBooked in advance, no urgency multiplier applied | $320 | $150 to $950 |
| Same dayOur band multiplied by 1.12 | $360 | $170 to $1,065 |
| Emergency calloutOur band multiplied by 1.35 | $430 | $205 to $1,285 |
Our estimate from national cost bands, not a quote from any business. Every row is the same band with the urgency multiplier the site applies everywhere else, so this table can never contradict the headline number. Ask for a written price before the work starts.
Who is licensed to do this work
In California the classification that squarely covers this is C-20 warm-air heating, ventilating and air-conditioning, and the register says who holds it. Every listing on this site shows the classification, the license number and the date we read it, with a link back to the register entry so you can check it against the state rather than against us.
Overlapping classifications exist and are labeled as overlapping rather than as a match: C-38 refrigeration, C-4 boiler, hot water heating and steam fitting, C-43 sheet metal and D-62 air and water balancing. A general building contractor may hold the job and subcontract the trade, which is a real answer and a different one, so the card says which of the two you are looking at.
One thing worth being plain about: CSLB classifications do not distinguish commercial work from residential. There is no separate commercial license to hold and no register field that would prove one. That is why this page describes the equipment rather than the contractor, and why nothing here says a business has been checked out. We read a public record on a stated date. That is the whole claim.
Before you pay for a callout
Two minutes of checks that sometimes end the problem
We would rather you did not need a callout at all. These are the checks that end the most calls for this fault.
Try a quick fix first
Some issues resolve without a truck roll. Two minutes now can save the callout.
- 1
Change the batteries if it takes them. A blank thermostat is a dead battery far more often than it is a dead system.
- 2
Check the schedule and any hold or lockout. Premises with staff turnover accumulate settings nobody remembers making, including holiday schedules that ran last year.
- 3
Feel where the thermostat is mounted. One in direct sun, above a fryer or beside a door reads the wrong temperature honestly, and moving it is the fix.
- 4
If the display is alive but nothing happens, look for a tripped safety at the unit rather than assuming the control failed.
What the visit actually includes
- Control diagnosis and wiring check at both ends
- Battery, sensor or display replacement
- Thermostat replacement matched to the equipment stages
- Schedule and setback programming
- Heat and cool cycle test after the work
Diagnosis
How thermostat faults usually present
Written from how these faults actually present on a working premises, not from a manual.
New smart thermostat, equipment now short cycles
Staged or heat-pump equipment wired to a control that does not match it. Common after a well-meant self-install, and it stresses the compressor.
Listed for this trade
Businesses listed for thermostat
Read from public license registers, so there is no ranking here and no distance: this page has no location to measure from. Enter your ZIP to sort by who is nearest to your site.
By location
Thermostat repair and replacement near you
Local pages show which businesses are listed for that metro, how far out they sit, and the local conditions that drive demand.
Counted from the businesses we have imported for each metro center inside a 25 mile radius, and counting only those whose own license classification names this trade. General contractors licensed widely enough to take it on and subcontract it are excluded here, and still appear in a search. A metro reads “none yet” until we load a register that covers this trade there.
All coverage areasQuestions owners ask
Thermostat FAQs
Short, specific answers. If yours is not here, ask the business you call before you agree to the visit.
Can I fit a thermostat myself?
On a simple single-stage system, often yes. On staged, heat-pump or multi-zone commercial equipment the wiring decides how the unit protects itself, and a wrong connection can damage a compressor.
Will a smart thermostat cut my bill?
Only through the schedule. The saving comes from not conditioning an empty building overnight, which any programmable control can do. Buy it for the schedule and the remote alarm, not for magic.
Is thermostat work licensed?
It sits under the C-20 air conditioning classification in California when it is done as part of the system. The listings here show which businesses hold it.
Related work
Often booked in the same visit
Batching jobs into one mobilization is the cheapest way to buy this kind of work.
Rooftop HVACRTU not cooling or heating, tripping breakers, noisy fans and belt failures.from $260Commercial ACWarm air from the vents, weak airflow, condensate leaks and thermostat faults.from $190Commercial heatingNo heat, short cycling, ignition lockouts and unit heater failures.from $210Split systemOutdoor condenser and indoor head faults, error codes, icing and drain leaks.from $200
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Ready when you are
Need thermostat sorted?
Search your ZIP to see the businesses listed for this trade nearest to your site, with the license numbers and phone numbers we hold, then call them yourself.
- Cost to search
- Free
- Account needed
- None
- Who you call
- The business