What it is
The contactor is the relay that closes to send power to your compressor and outdoor fan. It clicks every time your AC cycles, and eventually the contacts pit, burn or stick.
What you would notice
- A buzzing or chattering noise from the outdoor unit
- The outdoor unit will not start at all
- The unit runs continuously and will not shut off (stuck closed)
- Visible pitting or a burnt smell at the contacts
Can you do this yourself?
Pay a professional
A contactor is a high-voltage switch wired into the same panel as the capacitor. Same voltage, same risk, less upside. Pay for it, and pay a fair price.
What to say when you call
Red flags
- A contactor quote in the many hundreds
- Replacing the contactor without checking the capacitor while the panel is already open
The call-out alone runs $100–$250 before any work, plus $40–80/hr on top, evenings and weekends. A whole new system is $3,800–$7,500 — compare every quote to that.
Where these numbers come from
- Angi, AC contactor replacement cost — part $15–70, average installed ~$220
Did it turn out to be this?
Nobody has ever published how often an AC call turns out to be something cheap — the best figure available anywhere is one company's marketing page. So we are building it. No account, no email, and your ZIP is cut to three digits before it is sent.
← Every AC repair, with both numbers
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