Can a worn contactor stop my compressor starting?

Yes — a worn or pitted contactor is one of the more common reasons a compressor won’t start or starts intermittently. It’s an inexpensive part, so it’s usually checked before anything costly.

Should I replace the contactor when I replace the compressor?

Often, yes — ActronAir frequently recommends it, because a worn contactor can damage a new compressor. It’s cheap insurance to do both at once.

How do I get the right contactor?

Contactors are matched by rating, poles, coil voltage and auxiliary contacts. Send us your model number and we’ll confirm the correct genuine part.

ActronAir Contactors: A Practical Guide

Genuine ActronAir compressor contactor — Actron Spare Parts.

A contactor is the heavy-duty electrical switch that powers the compressor and other major components. When the system calls for cooling or heating, the contactor closes and lets mains power through; when it’s satisfied, it opens again. Because it switches under load thousands of times, the contacts wear — and a worn contactor is one of the more common causes of a compressor that won’t start. This guide explains what it does, the signs it’s failing, and how to get the right genuine part.

What an ActronAir Contactor Does

ActronAir uses quality contactors and relays — brands such as ABB and WEG — sized to the load:

Contactors — from mini contactors up to larger units (rated by kW, from around 3kW to 15kW at 240V), single- or multi-pole.
Interlock contactors — paired contactors that can’t close at the same time (used in reversing or staged arrangements).
Relays — lighter-duty switching for smaller loads.
Auxiliary contacts and link modules — add-ons that report status or link contactors together.
Capacitor-duty contactors and surge protectors — for specific switching and protection roles.

Signs Your Contactor May Be Worn

The compressor or outdoor unit won’t start, or starts intermittently.
A chattering or buzzing sound from the contactor when the system tries to start.
Visible wear — pitted, blackened, or welded contacts.
The system works sometimes and not others (a classic sign of worn contacts making poor connection).

Because a worn contactor and a failed compressor can look similar from the outside, a technician will check the simple, cheap part — the contactor — before condemning anything expensive.

A Genuine Trade Tip: Replace It With the Compressor

When a compressor is replaced, ActronAir often recommends replacing the compressor contactor at the same time — a worn contactor can damage a brand-new compressor, and it’s inexpensive insurance to do both together. If you’re replacing a compressor, ask us about the matching contactor.

ActronAir Contactor FAQs

Getting the Right Genuine Contactor

Contactors are matched by their electrical rating (kW/amps), pole configuration, coil voltage, and the auxiliary contacts required. Fitting the wrong rating is unsafe and won’t last. Send us your model number and we’ll confirm the right genuine part. Call 1300 904 554 or email actron@nationalacparts.com.au.

Getting the Right Genuine Contactor

We stock genuine ActronAir contactors, relays and auxiliaries, with same-day dispatch on stocked items ordered before 1:00 PM AEST. Browse the range on our Contactors page, or get in touch and we’ll match the right one.

ARC licence holder? Enter your promo code and licence number at checkout for your ARC discount on spare parts.