An A/C system that blows cold air for awhile then warm air is probably freezing up. This can be caused by air and moisture in the system that allows ice to form and block the orifice tube.
Air can get inside a system through leaks, by not evacuating the system prior to recharging it, and/or by recharging the system with refrigerant that is contaminated with air. Recovery equipment can suck air into the recycling tank if an A/C system contains air or if the system has a leak. For this reason, the refrigerant recovery tank on recycling equipment must be checked and purged daily. On some equipment, this is done automatically. But on equipment that lacks an automatic purge cycle, tank pressure and temperature has to be measured and compared to a static pressure reference chart.
My A/C isn’t as cold as it used to be, what’s going on?
There are several reasons a car A/C problem can arise and lose its cool. Visit your mechanic as soon as you start noticing this symptom, it could mean the difference between needing a small repair, or worse, a large one. Here’s what can cause your cold air to lose its cool.
The lack of precious cold air could be caused by:
• A Freon leak caused by a failed o-ring, seal, hose or component
• A clogged expansion tube or refrigerant charging hose
• Failed compressor or compressor clutch
• Failed blower motor or blower motor resistor
• Damaged or failed condenser or evaporator
• Vacuum leaks
• Failed switch, fuse, relay, control module, blend door or solenoid
Leaks can be devastating. When an A/C system develops a leak, you have what’s called an “open system.” If you or your technician discovers the leak early, your repair will be less expensive. Unfortunately, if a leak has been affecting your cold air for a while, moisture will most likely have entered your A/C system and may have damaged other vital and expensive parts.
What causes an A/C system leak?
Age and moisture. Plain and simple. Rubber seals and hoses can also lose their elasticity over time and breakdown allowing Freon to escape and moisture to enter your vehicle’s A/C system. Moisture is the kiss of death for your A/C system, mixing with refrigerant and creating a system destroying corrosive acid.
• Low refrigeration level can be rectified by re-filling the gas in the refrigerant tanks or fixing any noticeable leakage.
• A malfunctioning air conditioner system can be treated by a repair specialist who eliminates the growth of micro-organisms and restores fresh and vibrant car interiors.
• A clogged condenser can be cleaned by employing a good quality flushing agent that vaporizes quickly and does not leave residue in the system. Replace the condenser if it has been used for many years and giving frequent problems.
• Switch on the air conditioning unit and check if the compressor, compressor clutch switch, fuses, wires, fan belt and compressor seal are functioning adequately. Check whether the oil in the compressor has been contaminated. Flush the AC unit to replace the old oil with the new.
• For efficient working of the air conditioning unit, it is advised to regularly replace the expansion valve, accumulators and receiver driers.
• Upon confronting strange noises emanating from the air conditioning unit, skilled an air conditioner technician should be immediately contacted.
Attending to the air conditioning system can save car owners from the cumbersome process of replacing the unit, and paying unnecessary expenses.