145 Deakin St, Kurri Kurri NSW0403 941 480
Mark Ostermann's signwritten service ute parked beside a Caterpillar D6H bulldozer in hill country
Kurri Kurri, Hunter Valley

Air-con for the gear
that actually works.

Cars, trucks, tractors, mining and plant machinery. Mark Ostermann has been the bloke people around the coalfields ring when the air-con packs up, and most of the time he comes to the machine rather than the other way round.

4.8 from 30 Google reviewsLicensed and refrigerant certifiedOpen Saturday mornings
CarsTrucksTractorsMiningPlant MachineryCarsTrucksTractorsMiningPlant Machinery
CarsTrucksTractorsMiningPlant MachineryCarsTrucksTractorsMiningPlant Machinery
The short version

One trade, done all the way through.

Plenty of workshops will put a set of gauges on your car and give the air-con a squirt of gas. Fewer will pull a dash out to get at the heater box, make up a hose to length on the spot, or drive out to a paddock to sort a tractor that is not going anywhere.

That is the whole job here. Mark Ostermann Automotive Air-Conditioning is a specialist outfit in Kurri Kurri covering cars, trucks, tractors, mining and plant machinery, with the licences and refrigerant tickets to back it up.

If it has an air-conditioner and it has stopped being cold, it is worth a phone call.

CarsTrucksTractorsMiningPlant Machinery
Kubota M6800 tractor in a shed with the bonnet up and air-conditioning gauges connected
Gauges on a Kubota M6800 in the shed. Tractor cabs cop dust and heat that a car never sees, so they are their own kind of job.
What I do

Six things, written on the side of the ute.

No padding and no list of trades he does not actually do. This is the same list that is signwritten on the truck.

01

Servicing

A regular service keeps the gas where it should be and the compressor doing easy work. Booked in, done, back on the road.

02

Repairs

Blowing warm, cutting in and out, or making a noise it never used to make. Repaired properly rather than topped up and sent away.

03

Installations

A full air-conditioning system fitted to a vehicle or a machine that never had one, or a replacement for a system past saving.

04

Modifications

Systems adapted to suit the machine and the way it actually gets used. Older gear, odd fitments and one-off setups included.

05

Diagnosis

Finding the real fault first. Reviews here mention next-day bookings and problems pinned down fast, which is the point of doing it properly.

06

Mobile Specialist

The van comes to the machine. Paddocks, job sites, farm sheds and yards, so the gear does not have to be floated in to a workshop.

Not sure which one it is? That is what the diagnosis is for.

0403 941 480
Mobile specialist

The machine stays where it is.

Floating a backhoe or a dozer into town to fix an air-conditioner costs more than the repair. So the van turns up with the vacuum pump, the gauges, the scales and a generator, and the work happens where the machine is parked.

Dirt sites, farm sheds, paddocks and yards. It is the same standard of work as it would get on a workshop floor, just done on site.

  • Vacuum, evacuate and recharge on site
  • Plant and earthmoving cabs a car shop will not take on
  • Farm machinery through the hot end of the season
CASE backhoe loader on a dirt site with side panels open, gauges connected and a vacuum pump on the ground
Made, not ordered

Hoses crimped up on the spot.

A split air-con hose on an older machine is usually where a repair turns into a three week wait for a part that may not exist any more.

Not here. There are trays of fittings and ferrules in the van and a hydraulic crimper to match, so a hose gets made up to the right length with the right ends while you wait.

It is the difference between a machine back in the paddock this afternoon and one sitting idle until a part turns up.

Organiser trays of air-conditioning hose fittings and ferrules with a made up hose and crimping pliers
Hydraulic hose crimping tool closed onto an air-conditioning hose

Fittings, ferrules and the crimper that puts them together.

Diagnosis first

Finding the fault, not guessing at it.

Gas that keeps disappearing means something is letting it out. Air that is cold at the vent but never cools the cab usually means something else again. Two of the photos below are what those jobs actually look like once the covers come off.

A condenser removed from under a vehicle, completely matted with grey dust and lint

Blocked solid

A condenser packed with dust cannot shed heat, so the system runs hot and the cab never gets cold. No amount of gas fixes that.

A car with the entire dashboard removed down to the crossmember to reach the heater and air-conditioning box

All the way in

Some faults sit behind the whole dash. Taking one out and putting it back properly is a day nobody enjoys, but it is the only way to reach a heater box or an evaporator, and it gets done.

What people say

Straight talk gets mentioned a lot.

4.8from 30 reviews
on Google

Mark had a fair idea of what the problem would be, booked it in for the next day, and it turned out to be exactly what he thought. The car was completed promptly and at a reasonable price. Great service.

Garth EvaFebruary 2026

Amazing work , no nonsense, found the issue extremely fast and had it fixed and regassed in no time, my car aircon has been perfect. Highly recommend.

Matt TFebruary 2026

Mark is a master of his trade. No BS, he will tell you if there is a problem. He'll also have your AC shooting ice cubes for a good price. Highly recommend this man's services

Jace LambertDecember 2025

Diagnosed and fixed my cars air conditioning in under 24 hours and got me to come back when he heard a noise and fixed it straight away. Great knowledge, service and price. Would definitely recommend

Tania ChallinorAugust 2024
Licensed and ticketed

The numbers on the truck.

Handling refrigerant legally in Australia takes a licence, and repairing vehicles for a living takes another one. They are printed on the ute for anyone who wants to check them, so they are printed here too.

Mark Ostermann Automotive Air-Conditioning Pty Ltd, ABN 48 627 468 571.

Motor Vehicle Repairers LicenceMVRL No: 42803
Refrigerant Trading AuthorisationRTA No: AU12965
Refrigerant Handling LicenceRHL No: L025910
On the tools

A few more off the phone.

Two white Ford Falcons under a carport with bonnets up, one connected to gauges and a running vacuum pump
Mercedes-Benz engine bay with the front bar removed and the air-conditioning condenser exposed
The signwritten service ute in an industrial yard
Get in touch

Ring Mark. It is the quickest way.

Tell him what the vehicle or machine is and what it is doing, and he will tell you whether it is a quick one or a proper job.

Call or text0403 941 480
Workshop

145 Deakin St
Kurri Kurri NSW 2327

Opening hours
  • Monday8:00am - 5:00pm
  • Tuesday8:00am - 5:00pm
  • Wednesday8:00am - 5:00pm
  • Thursday8:00am - 5:00pm
  • Friday8:00am - 5:00pm
  • Saturday8:00am - 12:00pm
  • SundayClosed

Saturday mornings included, which is when most people notice the air-con is not working.

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