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Polar Express HVAC & Refrigeration

Air Conditioning

A smart thermostat is only as smart as its wiring.

Polar Express installs and repairs thermostats in homes across the San Antonio metro, with 24/7 emergency dispatch and same-day service on most repair calls. One flat-rate price is approved in writing before work begins for compatibility, common-wire power, staging, sensors, and app setup. TDLR license TACLA00127982C.

Most thermostat calls we take are not broken thermostats. They are missing common wires, wrong equipment settings, and staging nobody ever configured.

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  • Licensed TACLA00127982C
  • Since 2023
  • 4.9 Google rating

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A thermostat is a low-voltage switch with a very good screen on it, and almost every problem people bring us lives on the switch side rather than the screen side. The device needs constant power, which older homes frequently cannot supply because the conductor that carries it was never pulled through the wall. It has to be told what equipment it is controlling, and a heat pump told it is a furnace will do exactly the wrong thing on a cold morning. Multi-stage systems need their stages configured or they never use the low stage that made them efficient in the first place. Polar Express installs and sets up thermostats across San Antonio on whatever system you already own, and we treat the configuration as the real work, because that is the part deciding whether the thing was worth buying.

What we handle

Thermostats & Smart Controls covers more than one failure.

The complaint that gets called in is rarely the whole job. These are the things a technician is actually looking at on this equipment.

  • Replacement and upgrade

    Old mercury and mechanical stats, failed digital units, and upgrades from a basic programmable model to something you can actually reach from the road.

  • C-wire and low-voltage wiring

    Running a common wire, fitting an adapter where a new run is genuinely impossible, and repairing the corroded or nicked thermostat wire behind a lot of intermittent faults.

  • App setup and remote control

    Getting the device onto the network, into the right account, and genuinely usable by everyone in the house rather than only by whoever installed it.

  • Equipment compatibility and configuration

    Telling the thermostat what it is wired to: heat pump versus furnace, stage count, auxiliary heat lockouts, and fan behavior. This is where most bad installs go wrong.

  • Schedules and setback strategy

    Setbacks built for a Texas cooling season, so the system is never asked to drag a hot house down twelve degrees at five o'clock on the worst day of the year.

  • Sensors, zoning, and connectivity

    Remote room sensors for the bedroom that never matches the hallway, plus the network side of keeping a connected thermostat actually connected.

Signs and causes

What you are seeing, and what usually causes it.

Read these before you call. Knowing which one matches gets the right parts on the truck, and a couple of them are worth acting on in the next ten minutes.

  • The screen goes blank or the device resets itself

    A thermostat losing its display intermittently is almost always a power problem, and in most homes that means no dedicated common wire, so the device is stealing power through the cooling circuit. It is a wiring fix, and buying a second thermostat will not solve it.

  • The room is not the temperature the screen claims

    A thermostat mounted on an exterior wall, in direct sun, above a lamp, or over a supply run inside the wall cavity is reading its own little microclimate. Relocating it, or adding a remote sensor in a room that matters, fixes a complaint people normally blame on the air conditioner.

  • The system short cycles after a new thermostat went in

    Cycle rate, differential, and minimum run time are settings, and the factory defaults are not right for every system. Equipment that starts and stops every few minutes wears itself out and never dehumidifies, and the cause is configuration far more often than hardware.

  • Auxiliary or emergency heat runs when it should not

    On a heat pump, a thermostat that has not been told it is controlling a heat pump will bring on the expensive backup heat far too eagerly. In a mild climate that mistake stays invisible until the January bill lands on the counter.

  • Nobody else in the house can change the temperature

    A connected thermostat locked to one person's account or one phone becomes a household argument. Setup should include adding everyone who needs access, and showing people how to override a schedule at the wall without reaching for an app.

What it costs

You approve the price before the work starts.

Thermostat work splits cleanly into the device and the labor, and we keep those separate so you can see what you are paying for. Swapping a like-for-like unit where a common wire already reaches the wall is a short, simple job. Pulling new wire through a wall, fitting an adapter, or untangling a system that was mis-wired before we arrived takes longer and gets quoted accordingly. Either way the price is flat rate and approved first. You are also welcome to buy the thermostat yourself and have us install and configure it, and we will tell you before starting whether the model you picked can run your equipment properly.

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What moves the number

  • Whether a common wire already reaches the thermostat location
  • How difficult a new low-voltage run is in that particular wall
  • The type of system being controlled, from a single-stage unit to a multi-stage heat pump
  • How many thermostats and zones are at the address
  • Whether remote room sensors are part of the job, and where they go
  • Whether the thermostat is supplied by us or supplied by you

How the job runs

What happens between your call and a working system.

  1. Step 1

    Confirm compatibility before anything comes off the wall

    What the existing wiring actually carries, what the equipment is, and whether the model you want supports it. Five minutes here prevents the most common bad outcome, which is a thermostat that runs the system but runs it wrong.

  2. Step 2

    Wire it properly, including the common

    A dedicated common wire is the right answer anywhere the run allows one. Where it genuinely does not, an adapter at the air handler is a legitimate solution, and a thermostat quietly siphoning power through a valve is not.

  3. Step 3

    Configure the equipment settings

    Stage count, heat pump settings, fan behavior, cycle rate, and lockouts, all entered against the system you actually own. This step takes longer than the installation and it is the one that gets skipped.

  4. Step 4

    Set it up with you, not for you

    A schedule built around when the house is genuinely occupied, everyone who needs access added, and a plain explanation of how to override it. Then we watch a full cooling cycle before leaving.

Questions

Straight answers, before you call.

Still not covered here? The person who answers the phone can usually settle it in a sentence, day or night.

Call (210) 376-0781

The C-wire, or common wire, is the conductor giving a thermostat continuous low-voltage power instead of making it borrow power from the heating or cooling circuit. Smart thermostats need it because a screen and a radio draw far more current than an old mechanical stat ever did. Plenty of San Antonio homes built before smart thermostats existed do not have one connected, even when a spare unused wire is sitting right there in the wall.

It can, mostly by making setbacks happen reliably rather than by being clever. The savings come from not cooling an empty house, so a household that is home all day sees far less than one that leaves from eight to six. No thermostat can make a dirty coil or a leaking duct efficient, which is why we usually suggest handling those first if both are on the table.

Yes, and we check it against your equipment before it comes out of the box. The compatibility question that matters is not the brand, it is whether your system is single stage or multi stage, whether it is a heat pump, and what the existing wiring carries. If the model you bought cannot run your system properly, we would rather tell you that on the doorstep than install it and let you discover it in January.

Because a thermostat decides when the system runs and for how long, and its default settings rarely match the equipment underneath it. Cycle rate, differential, minimum off time, and stage timing all change what you feel in the room. A system that suddenly short cycles, overshoots, or leaves the house humid right after a thermostat swap is nearly always a configuration issue rather than a fault in the equipment.

They can be, and since the utility runs them rather than us, read the terms before enrolling. These programs generally offer an incentive in exchange for letting the utility adjust your thermostat briefly during peak demand events. Whether that trade works for your household comes down to who is home on a summer afternoon. We install and configure the equipment either way, and we do not administer any such program.

Polar Express provides one written flat-rate price for thermostat installation in San Antonio, approved before work begins. The price depends on whether a common wire already exists, the difficulty of any new low-voltage run, and the system type or number of zones being configured.

Polar Express offers same-day service on most thermostat repair calls across San Antonio, with 24/7 emergency dispatch when the control failure leaves a home without cooling or heat. The person answering the phone gives a real arrival window and asks about the display, system mode, wiring symptoms, and equipment response before dispatch.

Related services

The work that usually comes with this one.

Nearby

We run this service across the San Antonio metro. These are three of the areas we cover, and the full list lives on the service areas page.

One call, day or night.

Licensed, locally owned, and answering the phone around the clock. You get the diagnosis in plain language and the price before the work starts.

Call 24/7 · (210) 376-0781Book Service