FAQ

Do I need to be “in the trade” to deal with Highgate?

Yes. Highgate only markets its products to accredited air conditioning mechanics. For information on how to get licensed visit Arctick or to find a licensed mechanic visit Look For The Tick.

Why don’t we sell to the public?

Working on air conditioning systems in automotive vehicles requires skill and training. We only sell to accredited technicians to help maintain the quality of workmanship from the automotive industry.

How do I know my order has been shipped?

You will receive an email from us confirming the order has been collected and confirming consignment number details along with a link to click to track where your order is.

How long does delivery take?

Highgate Air offers 5 delivery runs per day to customers located in Adelaide metro. These runs leave at 7:30am, 10am, 12:30pm, 2pm and 3:30pm. We offer nationwide overnight delivery to our customers interstate.

I am in rural Australia, can you reach me?

Yes! We allow 2 days to deliver to remote areas, please click here to read a delivery testimonial from our customer in rural WA.

Do you price match?

Where the product is identical and in stock, Highgate will price match. Highgate reserves the right to refuse price matching for online only stores, or products sourced on ebay.

Does Highgate cater to the agricultural and mining industries as well?

Yes! Our breadth of range is vast – we have all the parts, tools and consumables needed for the AC needs of trucks, agricultural machinery, buses and mining equipment. We stock brands such as RedDot and Sigma, specifically designed to operate in extreme environments, like dust saturated atmospheres and extreme temperatures.

Do I need to do anything special to be ready to service cars R1234yf gas?

Yes! Check out our blog here for all you need to know about R1234yf.

How do you access the Highgate online store?

Are you an Accredited Trade Organisation? You need to be an accredited trade organisation that has a current ARC Licence and be operating and repairing air conditioning. You will need to hold an account with Highgate in order to access the Online Store. Register or login here. If you are having issues with your account or logging in, please call us on 1800 15 15 15.

How to register for an online access to the Highgate website?

If you are looking to register for online access to our website, please navigate to our Register Page by clicking here. Once on the Register page, please fill in all required fields, and click "Submit". Please note that after successfully submitting your registration request, you will receive a Credit Application Form which needs to be completed, printed, and posted or personally delivered to Highgate.

What causes a compressor with liquid slugging?

Usually caused by a TX valve stuck open, or incorrect TX valve. Too much refrigerant flowing into the evaporator will tend to ‘flood’ the coil so that liquid is returned to the compressor. Since liquid is, for all practical purposes, incompressible, liquid taken into the suction side of the compressor will cause serious physical damage to the valve plate and reed valves, and may even crack or break metal components. Liquid slugging may also be caused by allowing liquid refrigerant into the suction side during charging with the engine running.

What are the common causes of a clutch failure?

Clutches normally give long trouble-free service, and, like compressors, most problems are not inherent.
Common causes are:

• Voltage drop - clutches are designed to withstand sufficient torque in all normal conditions provided that the correct voltage is fed to the field coil (12-13.6v for 12 volt systems; 24-27v for 24 volt). Lower voltages will cause clutch slippage, especially when head pressure builds up
• Bearing failure - usually age, or heat due to slippage, compressor seize-up, etc
• Coil burn-out - usually caused by voltage problems, or heat from a slipping clutch
• Slippage - slippage is normally due to voltage drop (or incorrect voltage), oil on mating faces, compressor seize-up, clutch face wear, or too large an air gap
• Incorrect air-gap - the air gap between the field coil and rotor is automatically fixed. However, the air gap between the drive hub and the rotor is adjustable on some clutches, and it is critical that it is within recommended tolerance. Too big an air gap will cause slippage, too small will cause binding

Do you have TX Valve diagnosis tips?

• Valve stuck closed or blocked - almost no cooling and low pressure readings (may even be in a vacuum on the low side).
• Valve stuck open - poor cooling performance and high pressure readings on both sides of the system.
• Valve too small - poor cooling and low reading on low side.
• Valve too big - poor cooling and high reading on low side.
• Capillary damaged or incorrectly positioned. A damaged capillary or a capillary bulb not clamped to the evaporator outlet will result in the valve tending to stay open.
• Capillary incorrectly clamped or positioned in the cold part of coil will result in the valve tending to stay closed.

Is there a system oil charge calculation for larger systems?

The oil charge should be calculated on the amount of refrigerant required for the system, but the specifications and methods of calculation vary with compressor makes and models.
The simple guide below should obviate problems arising from insufficient lubricant where the manufacturer’s specifications are not available.

• Normal passenger systems: factory compressor oil charge.
• Dual or split systems:
  a) Add 15-20ml of oil for each additional evaporator or condenser coil.
  b) Add 3-4ml of oil for each additional metre of hose, over 5m (i.e., where total length of all hoses exceeds 5m).
• Rooftop systems: as for dual and split systems.
• Factory, or OE systems: check manufacturer’s specification and charge the system accordingly.
• Oil compensation: when a component has been replaced or flushed, oil will need to be added.
• The following guide may be helpful:
  Condenser: 25 - 40ml
  Drier: 15 - 30ml
  Accumulator: 30ml (plus the amount drained from the old accumulator)
  Evaporator: 25 - 40ml
  Hoses and pipes: 5 - 10ml per metre

Remember to add at least an equivalent amount of new oil to replace oil captured during the recovery process. This can be checked by draining or viewing the oil separator bottle on your recovery unit or automatic charging station.

• Variable compressors: with these types of compressors, it is increasingly critical to have the correct amount of oil in view of the control valve operating correctly. When installing a new compressor, it is recommended to completely flush the system to remove all old oil and ensure that the amount of oil is correct to the manufacturer’s recommendations within the replacement compressor.

Do you have a R134A pressure guide?

NOTE

At 0 rpm (system not operating), any major difference to the pressures shown indicates refrigerant is not R134a or is a mixture of multiple refrigerants. If pressure is 0, no refrigerant is present. The ambient engine compartment temperature must be taken into account when considering system pressures

important - explanatory notes on pressure guides

The above figures are a guide only, and some variation may occur on some systems, however, any substantial difference indicates a fault or problem. When testing an air conditioning system, full airflow across the condenser is essential. Extra fans, or other additional airflow may be necessary to simulate normal operating conditions, particularly if the vehicle has a viscous fan, or electric fans which are not activated when the compressor cuts in. It is good practice to charge a system by all of the following criteria:

• Correct amount of refrigerant for the system
• Normal pressures (gauge readings) on both sides of the system
• Correct temperature at the evaporator coil and acceptable temperature at the vents
• Normal condenser sub-cooling and superheat

‘Bomb charging’, or charging until the sight glass is clear, is probably the most common cause of over-charging and system damage. This method should not be used with any refrigerant. Technicians will have to be especially careful identifying the refrigerant now that a wide range of refrigerants and blends are in service as the static vapour pressure of R134a is very similar at normal ambient temperatures to other refrigerants.