What is an AC low-pressure hose?

The AC low-pressure hose carries refrigerant back from the evaporator inside the cabin to the compressor in the engine bay. Unlike the high-pressure hose, this line handles refrigerant at lower pressure but larger volume. If the hose develops a leak or blockage, the air conditioning system cannot cycle refrigerant properly, and cooling performance will drop.

Why do you need an AC low-pressure hose?

The low-pressure hose is a key part of the AC circuit. Without it, refrigerant cannot return to the compressor to be pressurised again, meaning the system won’t deliver cool air. A damaged hose can also cause refrigerant leaks, which reduce efficiency and put extra strain on other AC components such as the compressor.

Common signs your AC low-pressure hose needs replacing

• Air conditioning not blowing as cold as usual
• Visible oil or refrigerant leaks on or around the hose
• AC system losing refrigerant and needing frequent regassing
• Low suction pressure readings during an AC diagnostic test
• Hissing noises or reduced airflow when the AC is running

If you notice these symptoms, it’s likely the low-pressure hose is leaking or restricted and requires replacement.

What happens during an AC low-pressure hose replacement?

A mechanic will safely recover the refrigerant from the system, remove the faulty hose, and install a new low-pressure line matched to your vehicle. All O-rings and seals are replaced to prevent leaks. The AC system is then vacuum-tested, recharged with refrigerant, and checked to ensure strong, consistent cooling performance.

How much does an AC low-pressure hose replacement cost?

Replacing a low-pressure AC hose in New Zealand typically costs between $300 and $600, depending on the vehicle’s make and model. The price includes the new hose, refrigerant recharge, and labour. Premium or European vehicles may be at the higher end due to more complex AC layouts. You’ll receive an upfront quote before any repair work begins.

Is it safe to drive with a faulty AC low-pressure hose?

Yes, you can still drive the vehicle, but your AC system will not cool effectively, making summer driving uncomfortable. A leaking hose also allows refrigerant to escape, which can damage other parts of the air conditioning system if ignored. For comfort, system efficiency, and to protect your compressor, it’s best to replace the low-pressure hose promptly.