Air con leaking gas?

[slapout]

Some makes of air con have a check valve in the fill connection /port, this can be a good place to look for a small leak,

if the problem is found there its just a matter of installing a new valve, should be around 1000 +_ baht. It has a metal cap that screws on but unless it combined with a O ring and a seat for same it will allow gas to escape the system.

[Pib]

When I was young and stupid I tried some of those A/C Leak Stops and Engine Restorer products...they didn't work. Now that I'm old and a little smarter I laugh at some of my younger day use of such products. Now I will say that some of the consumer A/C Leak Stops do appear to stop leaks for while "if" the leaks are really small and in certain locations/materials; but generally, they are a short term bandage/snake oil.

[KittenKong]

One of my air-con units sprung a leak in Europe. The air coming out wasnt cold at all. The engineer pumped some air in and then sprayed soapy water on all the connections. He quickly found one that was leaking (by the bubbles). The screw thread had split along its length, presumably due to heating and cooling. He replaced the screw and remade the joint, and filled the system with gas and it was fine for many more years.

The engineer did say that the most likely place for a leak was in a joint, which made sense to me.

[Pib]

And an A/C leaks may not be continuous and/or only when they system is running. The leak may only occur at a certain temperature and pressure (and not necessarily a high pressure) and when the system is turned off. About 15 years ago I had car which had a slow freon leak...it would take about a month for enough freon to leak off to where the A/C wouldn't cool. I would take the car to a local military hobby shop where you could get your system leak checked and refilled pretty cheap...but if the shop tech found a leak in accordance with state law he would suck out all the freon until you got the leak fixed. The shop used a very good electronic leak detector. Now the shop tech never found a leak with the detector.

Anyway, on about my third trip to the shop to get a freon leak test and top-up (once again no leak detected) after I had turned the car off, the hood still up and the tech and I standing there for about 5 minutes talking about freon leaks and how hard they can be so very hard to detect sometimes there was a small hiss & a bubble come from the compressor outer case area...this only lasted a few seconds. The leak was right where where a big O-ring was fitted around the compressor casing...done at the factory...that area had been leak check numerous times while the compressor was operating and immediately after turning the car off. But never leaked checked say 5 or more minutes after turning off the car....or while the car was running

What was happening is the compressor would never leak under normal operating pressure/termperature...it would only leak when turned off, cooling down, and the freon reaching a certain pressure and maybe temperature--conditions had to be just right. Had that O-ring replaced in the compressor...leak was gone.

The Schrader valve where the freon is pressure checked/refilled is a common leak point as the rubber seal in the valve can dry-up after X-years and allow freon to leak...in addition to keep junk out of the valve that's another reason to ensure a tight fitting metal cap is placed on the valve after accessing the valve. And like KittenKong said, anywhere there is a joint.

[thai3]

.........pay.......pay.....pay.........

........I had one unit 'serviced' and cleaned 3 months ago.....he left some parts off.....the unit makes a strange sound now every 8 seconds....

...and my electric bill has been higher since....even during the cold spell...

how much were you charged? i paid 500 THB for gas and 800 THB for cleaning. mine was very dirty and it does run much better now. however he also left some parts off, in particlar the flaps that cycle side to side. maybe that is the strange sound you get every 8 seconds.

800 baht for clean one unit is very high we pay 250 and top up gas 3-400

[Dazinoz]

Hi,

First of all I would like to get a few terms straight. As someone mentioned Freon is a brand name of refrigerant and is like calling all pens Biros and tissues Kleenex, they are only brand names. Technically it is not a gas as during the refrigeration cycle the refrigerant is both a gas and a liquid. It can also be charged to a refrigeration unit as a gas or liquid. So the term I will use is refrigerant.

All cooling systems use a refrigerant and refrigerant can be many different types. Home fridges and smaller commercial unit are sealed units and refrigerant is added in the factory and piped welded. Therefor very rarely leak. This applies to single Ac window units.

Most AC installed in homes, etc are called split units with the compressor, a coil and a fan in the outside unit and a coil and a fan inside unit. The electronics can be in either or both units. These 2 units are joined by copper pipes. This is where the problem starts. The cutting, flaring and joining of the pipes is done by human hands, and as we all know, there is a significant variation in skills.

I had a split system in my bedroom in Australia for over 20 years and it never needed a top up. And really there is no reason that should not apply to all split units. Tools vary immensely. You need to cut the copper pipe with a good cutter and the de-bur. After that a good flare tool should be used. Some cheaper ones just squeeze the pipe and can be over squashed by the operator. I used a concentric roller type which rolled the pipe to a flare the had a cut out if I tried to put too much pressure. The joint should be made very carefully and a small amount refrigerant oil added both sides of the flare to help seal and prevent dragging of the copper pipe on the flare nut side.

As I mentioned there are many different types of refrigerants used. I have heard of ammonia being used and also LPG but obvious dangers in the latter. The main ones I used in Australia was R22, R410a, R407c and R134?( this mainly used in cars). R22 is being phased out due to its ozone depleting characteristics and being replace by mainly R410a in domestic units. This in itself causes more problems. R410a is a mixture of refrigerants and operates at higher pressures than the old common R22. It also has a smaller molecules size so can leak easier. More specialized tools and care needed in installation of units with this refrigerant. As well as the tools mentioned I also used torque wrench on the joints to prevents leaks and damage to the copper pipe. I then pressure tested the joints with nitrogen and 1.5x normal operation pressure.

If an R22 units leaks it can be topped up. R410a is a mixture of 2 refrigerants and if the unit leaks, especially during non operation the unit, 1 refrigerant can leak more then the other. It is recommended that if one of these units leak the remaining refrigerant is reclaimed and a new lot added.

Big cooling units control the amount of refrigerant flow by a Tx valve. These don't generally exist in a home unit to save on complexity and thus costs. So these units are "critically charged" with the correct amount of refrigerant for and installation of about 1 to 4 meters of piping. If longer piping is run extra refrigerant is required as per the manual. A unit can be overcharged with too much refrigerant and causes pressure problems.

I have raved a bit but how do you tell if not enough refrigerant? First is to check that the compressor in the outdoor unit is running when you try to cool the room. The fan should also be running. If they are both running look at the pipes coming from the outdoor unit. If the smaller one is icing up you are low on refrigerant. If not icing up feel with your hand and should be cold. If not cold, little or no refrigerant. Another things is that refrigerant oil travels around the system with the refrigerant. So if there is a leak oil leaks too. You can unwrap the insulation of each of the connection and see if you can spot oil.

Hope this helps.

[johnarno]

My cousin is a fridge/aircon engineer in UK. here on holiday, he says Freon is the gas, and he uses Leak Seal pressureised cans to stop the leaks, it comes with all the fittings and you connect it to the low pressure side of the aircon system and it pushes the sealant in, but it will only work if it is a small leak. He says if you have to keep re-gassing your unit, it definately has a leak.

[yankee99]

Instead of using some backyard ac mechanic get authorized Mitsubishi service +6627637000 i think its 1500 baht plus parts. You will see the difference as soon as they arrive!

[Dazinoz]

From Wikipedia.

Freon is a registered trademark of The Chemours Company, which it uses for a number of halocarbon products. They are stable, nonflammable, moderately toxic gases or liquids which have typically been used as refrigerants and as aerosol propellants. These include the chlorofluorocarbons (CFCs) that cause ozone depletion (such as chlorodifluoromethane), but also include newer refrigerants which typically include fluorine instead of chlorine and do not deplete the ozone layer. Not all refrigerant is labelled as "Freon" since Freon is a brand name for the refrigerants R-12, R-13B1, R-22, R-502, and R-503 manufactured by The Chemours Company.

[whaleboneman]

What kind of torque wrench were you using on tube fittings?

[Jomtien9999]

They only want make some more money.. I have a sniffer , can take micro leak....

[F4UCorsair]

gas

Refrigerants make air conditioning possible. Contained within the coils of an air conditioner, these liquid agents cool and dehumidify indoor air. For years, the most common refrigerant gas used in air-conditioning systems was R-22 (Freon).

still is R22 here as far as I know

Your last quote was AC do not use gas anymore, and now its changed that they use gas.

That Freon must be giving you a blast from the past.

You lack a grasp of English usage, and it's possible English is not your mother tongue.

Airconditioners do not use gas, I.e., in normal operation, no gas is 'burnt' or otherwise used up/ expended, as gasoline is in an internal combustion engine.

Freon is 'used' in airconditioners, and in this sense it means freon is the gas 'employed' (is required) in the operation.

Of course it's possible you're just being a smart

Ar $ e??

Edited April 16, 2016 by F4UCorsair

[Rough Rider]

Just some questions that you can answer,

1) Is the big size pipe[ Suction side to the compressor] building ice up on it? If yes then it is low on gas as the temperature on the intake side to the compressor is lower than 0 deg C and need to be top up with gas.

The temperature should be around 5 deg C

2) Is the Condenser [ Cooling unit} building ice up on it ? If yes then it is low on gas.

3) Is the cooling unit blowing out normal room temperature air while it is supposedly been cold air.? Then the unit has leaked out plenty gas and can not do the cooling. Short on gas.

4) Nextime he do the service tell him to use soap water and a paint brush to see were the leak is or use a propane leak detector to see where the leak is.

If there is a leak the blue flame of the propane leak detector will change from blue to a green flame as it pick up were the leak is.

[Rough Rider]

Hi,

First of all I would like to get a few terms straight. As someone mentioned Freon is a brand name of refrigerant and is like calling all pens Biros and tissues Kleenex, they are only brand names. Technically it is not a gas as during the refrigeration cycle the refrigerant is both a gas and a liquid. It can also be charged to a refrigeration unit as a gas or liquid. So the term I will use is refrigerant.

All cooling systems use a refrigerant and refrigerant can be many different types. Home fridges and smaller commercial unit are sealed units and refrigerant is added in the factory and piped welded. Therefor very rarely leak. This applies to single Ac window units.

Most AC installed in homes, etc are called split units with the compressor, a coil and a fan in the outside unit and a coil and a fan inside unit. The electronics can be in either or both units. These 2 units are joined by copper pipes. This is where the problem starts. The cutting, flaring and joining of the pipes is done by human hands, and as we all know, there is a significant variation in skills.

I had a split system in my bedroom in Australia for over 20 years and it never needed a top up. And really there is no reason that should not apply to all split units. Tools vary immensely. You need to cut the copper pipe with a good cutter and the de-bur. After that a good flare tool should be used. Some cheaper ones just squeeze the pipe and can be over squashed by the operator. I used a concentric roller type which rolled the pipe to a flare the had a cut out if I tried to put too much pressure. The joint should be made very carefully and a small amount refrigerant oil added both sides of the flare to help seal and prevent dragging of the copper pipe on the flare nut side.

As I mentioned there are many different types of refrigerants used. I have heard of ammonia being used and also LPG but obvious dangers in the latter. The main ones I used in Australia was R22, R410a, R407c and R134?( this mainly used in cars). R22 is being phased out due to its ozone depleting characteristics and being replace by mainly R410a in domestic units. This in itself causes more problems. R410a is a mixture of refrigerants and operates at higher pressures than the old common R22. It also has a smaller molecules size so can leak easier. More specialized tools and care needed in installation of units with this refrigerant. As well as the tools mentioned I also used torque wrench on the joints to prevents leaks and damage to the copper pipe. I then pressure tested the joints with nitrogen and 1.5x normal operation pressure.

If an R22 units leaks it can be topped up. R410a is a mixture of 2 refrigerants and if the unit leaks, especially during non operation the unit, 1 refrigerant can leak more then the other. It is recommended that if one of these units leak the remaining refrigerant is reclaimed and a new lot added.

Big cooling units control the amount of refrigerant flow by a Tx valve. These don't generally exist in a home unit to save on complexity and thus costs. So these units are "critically charged" with the correct amount of refrigerant for and installation of about 1 to 4 meters of piping. If longer piping is run extra refrigerant is required as per the manual. A unit can be overcharged with too much refrigerant and causes pressure problems.

I have raved a bit but how do you tell if not enough refrigerant? First is to check that the compressor in the outdoor unit is running when you try to cool the room. The fan should also be running. If they are both running look at the pipes coming from the outdoor unit. If the smaller one is icing up you are low on refrigerant. If not icing up feel with your hand and should be cold. If not cold, little or no refrigerant. Another things is that refrigerant oil travels around the system with the refrigerant. So if there is a leak oil leaks too. You can unwrap the insulation of each of the connection and see if you can spot oil.

Hope this helps.

[Dazinoz]

What kind of torque wrench were you using on tube fittings?

Hi, if you were asking me it was a special torque wrench set with flare nut spanner attachments bought from a large refrigeration supply shop.

Something like this.

But with open ended flare nut spanners like these.

Oooops. Photos did not appear!!!

Edited April 16, 2016 by Dazinoz

[Farmer1956]

My take if it puts out cold air your in good shape.If not you most likely have A small leak.You'll most likely need to get A new one sooner than later.The heat in Thailand puts A strain on air conditioners.

I would hope not if the A/C is only 3 years old...plus it's a Mitsubishi Heavy Industries A/C which is suppose to be better/longer lasting than a regular Mitsubishi A/C. Heck I have 7 York A/Cs in my house...these A/Cs are eight years old....never had to have freon added to any of them due to leaks.

I suggest getting your air-con system pressure tested, this should identify if you have a leak or not. A 3 year old system should not be giving problems, but there are exceptions. Check the unions, a seal could be perished or split which may allow coolant to leak out.

There is the possibility that you are being scammed though.

If your system appears to be working efficiently, the likelihood is that there is nothing wrong with it.

[Rough Rider]

Just some corrections on your quote. Under pressure all refrigerants and all type of type of gas is a liquid and under atmospheric pressure turned out to be a gas (except Freon 11 which is a liquid refrigerant) further more the small pipe is the liquid line and is high pressure and will never ice up ("If the smaller one is icing up you are low on refrigerant") It is the bigger size pipe that is the suction side with gas and low pressure that can ice up. Normally wrapt in a none drip tape. You mention the following ". I have heard of ammonia being used and also LPG but obvious dangers in the latter." Well Ammonia is used in the fridges that is portable and used in caravan fridges and works with a small flame that heats up the ammonia and in the process separates the water from the ammonia and the gas released is the refrigerant that does the cooling through the system. LPG was never used as a refrigerant as it does not have cooling properties.

Hi,

First of all I would like to get a few terms straight. As someone mentioned Freon is a brand name of refrigerant and is like calling all pens Biros and tissues Kleenex, they are only brand names. Technically it is not a gas as during the refrigeration cycle the refrigerant is both a gas and a liquid. It can also be charged to a refrigeration unit as a gas or liquid. So the term I will use is refrigerant.

All cooling systems use a refrigerant and refrigerant can be many different types. Home fridges and smaller commercial unit are sealed units and refrigerant is added in the factory and piped welded. Therefor very rarely leak. This applies to single Ac window units.

Most AC installed in homes, etc are called split units with the compressor, a coil and a fan in the outside unit and a coil and a fan inside unit. The electronics can be in either or both units. These 2 units are joined by copper pipes. This is where the problem starts. The cutting, flaring and joining of the pipes is done by human hands, and as we all know, there is a significant variation in skills.

I had a split system in my bedroom in Australia for over 20 years and it never needed a top up. And really there is no reason that should not apply to all split units. Tools vary immensely. You need to cut the copper pipe with a good cutter and the de-bur. After that a good flare tool should be used. Some cheaper ones just squeeze the pipe and can be over squashed by the operator. I used a concentric roller type which rolled the pipe to a flare the had a cut out if I tried to put too much pressure. The joint should be made very carefully and a small amount refrigerant oil added both sides of the flare to help seal and prevent dragging of the copper pipe on the flare nut side.

As I mentioned there are many different types of refrigerants used. I have heard of ammonia being used and also LPG but obvious dangers in the latter. The main ones I used in Australia was R22, R410a, R407c and R134?( this mainly used in cars). R22 is being phased out due to its ozone depleting characteristics and being replace by mainly R410a in domestic units. This in itself causes more problems. R410a is a mixture of refrigerants and operates at higher pressures than the old common R22. It also has a smaller molecules size so can leak easier. More specialized tools and care needed in installation of units with this refrigerant. As well as the tools mentioned I also used torque wrench on the joints to prevents leaks and damage to the copper pipe. I then pressure tested the joints with nitrogen and 1.5x normal operation pressure.

If an R22 units leaks it can be topped up. R410a is a mixture of 2 refrigerants and if the unit leaks, especially during non operation the unit, 1 refrigerant can leak more then the other. It is recommended that if one of these units leak the remaining refrigerant is reclaimed and a new lot added.

Big cooling units control the amount of refrigerant flow by a Tx valve. These don't generally exist in a home unit to save on complexity and thus costs. So these units are "critically charged" with the correct amount of refrigerant for and installation of about 1 to 4 meters of piping. If longer piping is run extra refrigerant is required as per the manual. A unit can be overcharged with too much refrigerant and causes pressure problems.

I have raved a bit but how do you tell if not enough refrigerant? First is to check that the compressor in the outdoor unit is running when you try to cool the room. The fan should also be running. If they are both running look at the pipes coming from the outdoor unit. If the smaller one is icing up you are low on refrigerant. If not icing up feel with your hand and should be cold. If not cold, little or no refrigerant. Another things is that refrigerant oil travels around the system with the refrigerant. So if there is a leak oil leaks too. You can unwrap the insulation of each of the connection and see if you can spot oil.

Hope this helps.

[soc]

Hi,

First of all I would like to get a few terms straight. As someone mentioned Freon is a brand name of refrigerant and is like calling all pens Biros and tissues Kleenex, they are only brand names. Technically it is not a gas as during the refrigeration cycle the refrigerant is both a gas and a liquid. It can also be charged to a refrigeration unit as a gas or liquid. So the term I will use is refrigerant.

All cooling systems use a refrigerant and refrigerant can be many different types. Home fridges and smaller commercial unit are sealed units and refrigerant is added in the factory and piped welded. Therefor very rarely leak. This applies to single Ac window units.

Most AC installed in homes, etc are called split units with the compressor, a coil and a fan in the outside unit and a coil and a fan inside unit. The electronics can be in either or both units. These 2 units are joined by copper pipes. This is where the problem starts. The cutting, flaring and joining of the pipes is done by human hands, and as we all know, there is a significant variation in skills.

I had a split system in my bedroom in Australia for over 20 years and it never needed a top up. And really there is no reason that should not apply to all split units. Tools vary immensely. You need to cut the copper pipe with a good cutter and the de-bur. After that a good flare tool should be used. Some cheaper ones just squeeze the pipe and can be over squashed by the operator. I used a concentric roller type which rolled the pipe to a flare the had a cut out if I tried to put too much pressure. The joint should be made very carefully and a small amount refrigerant oil added both sides of the flare to help seal and prevent dragging of the copper pipe on the flare nut side.

As I mentioned there are many different types of refrigerants used. I have heard of ammonia being used and also LPG but obvious dangers in the latter. The main ones I used in Australia was R22, R410a, R407c and R134?( this mainly used in cars). R22 is being phased out due to its ozone depleting characteristics and being replace by mainly R410a in domestic units. This in itself causes more problems. R410a is a mixture of refrigerants and operates at higher pressures than the old common R22. It also has a smaller molecules size so can leak easier. More specialized tools and care needed in installation of units with this refrigerant. As well as the tools mentioned I also used torque wrench on the joints to prevents leaks and damage to the copper pipe. I then pressure tested the joints with nitrogen and 1.5x normal operation pressure.

If an R22 units leaks it can be topped up. R410a is a mixture of 2 refrigerants and if the unit leaks, especially during non operation the unit, 1 refrigerant can leak more then the other. It is recommended that if one of these units leak the remaining refrigerant is reclaimed and a new lot added.

Big cooling units control the amount of refrigerant flow by a Tx valve. These don't generally exist in a home unit to save on complexity and thus costs. So these units are "critically charged" with the correct amount of refrigerant for and installation of about 1 to 4 meters of piping. If longer piping is run extra refrigerant is required as per the manual. A unit can be overcharged with too much refrigerant and causes pressure problems.

I have raved a bit but how do you tell if not enough refrigerant? First is to check that the compressor in the outdoor unit is running when you try to cool the room. The fan should also be running. If they are both running look at the pipes coming from the outdoor unit. If the smaller one is icing up you are low on refrigerant. If not icing up feel with your hand and should be cold. If not cold, little or no refrigerant. Another things is that refrigerant oil travels around the system with the refrigerant. So if there is a leak oil leaks too. You can unwrap the insulation of each of the connection and see if you can spot oil.

Hope this helps.

Bravo, excellent post.

l worked on a minesite in Australia & my forté was air conditioning of heavy mobile equipment.

Only thing l could add was that after draining the Nitrogen & vacuuming the system, l would immerse the gas container in very hot water(especially in winter) while the hoses were connected then open the valve wide, so that the gas was sucked into the system very rapidly.

lmmediately start the engine & get the A/C working to assist in drawing in the gas.

And you are correct as to the cooling properties of LPG gas, but it is very dangerous & illegal to use.

l have a LandCruiser at home that uses R12 refrigerant. Thankfully has never leaked as if it ever does, l will have to convert the system, by law, to run on R134 which is no-where near as efficient.

A pleasure to read your post.

Cheers.

Edited April 16, 2016 by soc

[Dazinoz]

Bravo, excellent post.

l worked on a minesite in Australia & my forté was air conditioning of heavy mobile equipment.

Only thing l could add was that after draining the Nitrogen & vacuuming the system, l would immerse the gas container in very hot water(especially in winter) while the hoses were connected then open the valve wide, so that the gas was sucked into the system very rapidly.

lmmediately start the engine & get the A/C working to assist in drawing in the gas.

And you are correct as to the cooling properties of LPG gas, but it is very dangerous & illegal to use.

l have a LandCruiser at home that uses R12 refrigerant. Thankfully has never leaked as if it ever does, l will have to convert the system, by law, to run on R134 which is no-where near as efficient.

A pleasure to read your post.

Cheers.

Thanks for the kind words

Edited April 16, 2016 by Dazinoz

[Isan Farang]

gas

Refrigerants make air conditioning possible. Contained within the coils of an air conditioner, these liquid agents cool and dehumidify indoor air. For years, the most common refrigerant gas used in air-conditioning systems was R-22 (Freon).

still is R22 here as far as I know

Your last quote was AC do not use gas anymore, and now its changed that they use gas.

That Freon must be giving you a blast from the past.

You lack a grasp of English usage, and it's possible English is not your mother tongue.

Airconditioners do not use gas, I.e., in normal operation, no gas is 'burnt' or otherwise used up/ expended, as gasoline is in an internal combustion engine.

Freon is 'used' in airconditioners, and in this sense it means freon is the gas 'employed' (is required) in the operation.

Of course it's possible you're just being a smart

Ar $ e??

I know nothing I am from Barcelona

[JAS21]

.........pay.......pay.....pay.........

........I had one unit 'serviced' and cleaned 3 months ago.....he left some parts off.....the unit makes a strange sound now every 8 seconds....

...and my electric bill has been higher since....even during the cold spell...

how much were you charged? i paid 500 THB for gas and 800 THB for cleaning. mine was very dirty and it does run much better now. however he also left some parts off, in particlar the flaps that cycle side to side. maybe that is the strange sound you get every 8 seconds.

800 baht for clean one unit is very high we pay 250 and top up gas 3-400

You don't live in BK area then ...if you do tell me who!

[thai3]

Thanks for the interesting and helpful replies.

[Crossy]

.........pay.......pay.....pay.........

........I had one unit 'serviced' and cleaned 3 months ago.....he left some parts off.....the unit makes a strange sound now every 8 seconds....

...and my electric bill has been higher since....even during the cold spell...

how much were you charged? i paid 500 THB for gas and 800 THB for cleaning. mine was very dirty and it does run much better now. however he also left some parts off, in particlar the flaps that cycle side to side. maybe that is the strange sound you get every 8 seconds.

800 baht for clean one unit is very high we pay 250 and top up gas 3-400

You don't live in BK area then ...if you do tell me who!

We're a tiny bit further out of BKK than JAS, 500 to clean each unit (no discount for multiple units). Known the guys for many years, trust them (Warning Will Robinson, warning)

[bazza40]

I'd advise you get a new air con repairman from one of the bigger companies like homepro, Intercool or call Mitsubishi themselves. Insist the repair man disconnects and reconnects all connenctions as those will likely be the leaky points.

If its leaking from the compressor casing itself you'll need to replace. Most give 5 year warrentee on compressor.

Any service person worth their salt would be testing for leaks throughout the system after recharging with refrigerant. If they are not doing this, change to one that will.

Air conditioners should be run regularly to maintain seals in the system. Starting up an aircon after 3 months sitting idle can contribute to leakage problems.

The various refrigerant types, generally known as chlorofluorocarbons, are excellent solvents and hence can attack seals in the system.

Some chlorofluorocarbons such as Freon R12 are supposed to be banned as per the Montreal Protocol due to their ozone-depleting potential. China and Russia are not signatories. Don't know if Thailand signed off.

Edited April 16, 2016 by bazza40

[Thaimike370]

In the UK I used a dye to show a gas leak if I could not find it with a gas detector, useful for a very slow long term leak, it used to leave a yellow stain.

[Naam]

300 Baht per unit for an excellent job. reason for low price is quantity discount.

[Gonsalviz]

Never heard of a product that will seal the leak. Seams it would lock up the compressor as well. I have heard of them injecting something with a die to help locate the leak.

http://contractingbusiness.com/refrigeration/how-and-when-use-refrigeration-system-sealants

i didn't open your link but I can tell you there are products called engine restore that claim to restore compression ratio )blow by) and they are a complete waste of money.

It is called heavier oil.

[Pib]

Heavier oil....a method still used by "used" vehicle dealerships and private sellers to minimize engine smoke...help mask worn engine components such as rings, value guides, etc.

And people who bought a used vehicle wonder why their car exhaust smokes more after changing the oil.

Don't get me wrong...got nothing against buying used vehicles. With the exception of one new car I bought I have always bought used cars for my personal use. A person just has to accomplish due diligence in thoroughly checking out a used vehicle before buying...and even then they can still end up with a lemon.

[teatree]

It seems to be a common con here for a/c maintenance guys to claim the gas is low and to 'top it up' without actually doing anything.

If the A/C was fitted properly it should never need more gas as it is a closed system. Any need for more gas means there is a leak which needs fixing.

[Pib]

It's a con similar to auto repair/tire shops when they tell you your tires are over 3 years old and are now dangerous to use...best buy new tires--from them of course.