My thermostat says cooling but nothing happens. What now?
When your thermostat says Cooling but nothing in the house responds, no blower, no air movement, no sound from outside, the problem sits further back than either half of the system. That's different from one side running while the other stays quiet. Total silence usually means power or signal never reached the equipment at all: a tripped breaker for the air handler, a blown low-voltage fuse, or a safety switch that shut the whole system down. A few checks are safe to make before calling.
A Call for Cooling Isn't the Same as a System That Answers
Every time your thermostat asks for cooling, it sends a small low-voltage signal out to the equipment. It isn't cooling anything itself. Normally that signal reaches the air handler, the blower spins up, and a moment later the outdoor unit joins in. When your thermostat says Cooling and nothing happens anywhere in that chain, the gap isn't between the indoor and outdoor sides. It's earlier than that: the call is going out, but nothing downstream is receiving it, or nothing downstream has the power to act on it.
That's worth separating from a more common complaint, an indoor unit that runs while the outdoor unit stays silent. In that case the blower is clearly getting power and a signal of its own, and the missing link sits specifically in the outdoor unit's chain. Total silence is a different animal. If the blower never even attempts to start, the fault usually lives somewhere both halves of the system depend on together: the power feeding the air handler itself, a fuse guarding the low-voltage circuit, or a safety switch that cut things off before either side could start.
Why a Lit Screen Doesn't Mean the Signal Got Through
It can be confusing that the thermostat itself still looks alive, screen lit, showing Cooling, seemingly working fine, while the rest of the house stays silent. A battery-powered thermostat keeps its screen lit no matter what the equipment is doing, because nothing about its display depends on the air handler. A hardwired thermostat is different: its 24 volts comes from a transformer inside the air handler, on the same circuit that feeds the blower, so a lit screen on that kind of thermostat means at least that much of the chain is alive. Either way, a lit screen only tells you the thermostat has power. It cannot tell you whether anything received the call.
A blown low-voltage fuse is one of the more common reasons for exactly that kind of standoff. A small fuse on the equipment's control board protects that low-voltage circuit from a short. When it blows, nothing downstream can act on a call for cooling. A thermostat running on batteries keeps showing Cooling right through it. A thermostat powered from the equipment usually goes dark instead, which is a clue in itself. A tripped safety switch inside the system can produce a similar disconnect, cutting power to protect a part before it fails.
What's Safe to Check Before You Call
A short list is worth working through first. Confirm the thermostat is actually set to cool, not off or heat, and that the fan is set to auto rather than on, since it's an easy setting to bump by accident. If your thermostat runs on batteries, try a fresh set. Then find the breaker for your air handler in the electrical panel, not the outdoor unit's breaker, which is often a separate one, switch it off, then back on, once.
Set the thermostat back to cool afterward and give the system a few minutes to respond. If the blower starts and the system runs normally, good, though a breaker that tripped is still worth mentioning at your next maintenance visit. If it trips again right away, or nothing changes at all, stop there. That's your answer for tonight: whatever cut the signal isn't something a second or third reset is going to fix.
When It's a Job for a Meter, Not Another Guess
Total silence with a breaker that holds points to something inside the equipment: a blown low-voltage fuse, a failed transformer, a tripped internal safety switch, or a break somewhere in the wiring between the thermostat and the equipment. None of those are visible from outside a panel, and a thermostat display that's already told you everything it knows won't fix any of it on its own. If you notice a burning smell anywhere near the equipment, skip the troubleshooting entirely: shut the system off and call right away.
A licensed AC repair visit starts with a $150 service call and an upfront quote before any part gets replaced, so a technician can trace the actual break in the chain instead of swapping parts to see what sticks.
Thermostat Says Cooling But the House Stays Silent? Let's Trace It
Call or text (239) 350-5234. Tyler, Guiseppi, or someone from their team responds in under 3 hours on average during business hours, and after-hours calls are welcome for a $125 call-out fee.