What causes Aircon Gas Leak?

Your aircon shouldn't leak gas at all; if it was properly set up, gas will not leak even after 10-20 years!

Now, lets take a good look at high risk areas where gas leaks often occur.

1) At the locking nut area.

















               


Located at the condenser, you'll see all these nuts. Some condenser have a cover so you may not see them. These nuts
must be properly tightened. If they are not properly tightened, gas can leak from there.

Note: We were very surprised to find these nuts hand tightened, and subsequently running out of gas. After hearing from
customers over and over again that gas leak happened after some guys came to service the aircon, we find it hard to
believe but have to conclude that these may be cases of deliberate sabotage.

No wonder we kept getting calls asking " How much do you charge to service 3 aircon and top up the gas?"

Honestly, i'm still getting pretty upset when such questions were raised. Firstly, general servicing is not effective and
secondly, you shouldn't be topping up gas at all.

2) At the flare joints.
























As seen from the pictures above, the soft copper pipe were shaped into a flare (by using a fare tool). This allows a nut to
be inserted and finally tightened onto a screw threaded copper pipe.

Since the copper pipe is soft , once tightened, it forms a very good seal. But over tightening can cause it to crack.














Great care must be taken when forming the flare; if the flare is not formed well, with ripples, it may cause gas leak too.

Thus, if it leaks from here, it is caused by poor workmanship and not sabotage, DO NOT conduct chemical cleaning by
dismantling the entire fan coil. You will risk damaging the flare joints and subsequently leading to gas leak. You may like
to read up on keeping your copper pipes.

3) Inside the condenser

If any 2 pieces of copper pipes were accidentally touching one another, the vibration caused by the compressor can soon
rupture a hole in the pipes, causing gas leak. Since the pressure inside the condenser is a lot higher (~250psi) when
compressor is running, a leak in the condenser will usually be fast, at most 1 week and it'll all leak out. PS: the pressure of
your car tire is only ~30psi

The compressor sits on top of 3 pieces of rubber shock absorbers. Since the compressor is hot, and if the shock
absorber is made of inferior quality, it may melt or soften. This will cause the compressor to either tilt to one side of simply
lower by an inch. It is often this condition that causes two pipes to touch one another.

When technician had over charged the gas system, it causes the compressor to overheat, thus damaging the shock
absorbers. On top of that, an over charged system causes the compressor to vibrate vigorously, thus touching pipes that
were marginally apart.

3) It leaks at the pipes.

For details, please read keeping your copper pipes.

The rate of gas leak:

a) It leaks every few years.

If it runs out of gas every few years, it is a really tiny gas leak. Don't bother conducting pressure test nor an other sort of
test, its not worth spending that kind of money. Assuming your aircon will last you 10 years, so at most you'll top it up 10
times. Troubleshooting and replacing the pipes will cause you more than that. Don't worry, modern refrigerant gas is not
flammable and is not harmful to the human body unless taken in huge amount ( i mean really HUGE amount). In the olden
days, ammonia gas was used as refrigerant and this gas is highly toxic (fatal), but those are history.
.
b) It leaks in a couple of months time.

This rate of leak is definitely disturbing and most likely frustrating. But technically speaking, this is still a very small leak
and any attempt to isolate the problem (not pin point) will be very costly especially if it is a multi split aircon. If you are
lucky, it leaks at places that are not concealed.  There will be traces of oil at the place of leak. If leak can be picked up
visually, all it takes is to spot weld the leak and recharge the gas, total repair cost will be $78/hr (inspection) + blazing
($168), gas recharge ($69 to $129), total ~$350.

But, If visual inspection cannot detect any traces of oil, the leak might be occurring in the concealed copper pipes.
Pressure testing ($178 per set of pipe) will need at least half a day before we see any significant drop in gas pressure.

Note: your condenser liquefies the refrigerant gas by compressing said gas by ~600 times. Therefore, if we conduct
pressure test by using compressed air instead of liquefied gas, the rate of leak will "improved" significantly by
approximately 600 times. Therefore, what that took 90 days (2160 hours) to leak can be revealed in ~2160/600 = ~3.5
hours.

Therefore, we come in, set it up and back in the evening to monitor if pressure drops. But such test can only isolate which
pipe and blower set is leaking, it does not pin point. If you want to further isolate whether it is the pipe or blower, the
pressure test must be repeated at $178, and another day without aircon.

If it leaks at the connecting pipes, the pipes must be replaced. Depending on whether you want to run the new pipes
concealed or externally (with casing), pipe replacement is not cheap, and depending on the level of difficulty, pipe
replacement, will cost a minimum of $300 - $500.

But, the test itself (assuming a system 4) would have cost you $890. Making total repair cost ~$1500.

Therefore, gas leak can be a very painful experience for any house owner. Always avoid dismantling your air conditioner
for chemical cleaning, gas leak is not something you'll like to experience.

c) It leaks in a few days.

This is better indeed, leak will most likely be occuring in the condenser and can easily be picked up visually. Provided that
it leaks at copper pipe sections and accessible, all it takes is to spot weld the leak and recharge the gas, total repair cost
will be $78 (inspection) + blazing ($168), gas recharge ($69 to $129), total ~$350.
Copyright © 2011 Aircon Astiquer
Description of the faulty flare:

The nut which i'm holding was overly tightened,
causing the flare to crack. The pipe which is ~1mm
thick is now so compressed; the flare is in fact razer
sharp!
Picture of the nuts removed. The 'o-ring' seal will
leak after some years. Therefore, the outer nut is
vital to be properly tightened.
Call Kevin @ 90674867
Aircon Astiquerair conditioning Specialist
biz. reg. no: 52959937J