[frank otero]

Situation: Trane A/C, less than 4 years old, began to loose gas about a year after installation. The company came out one time - could not find the leak topped off system, paid for service. 7 - 8 months later, low gas, changed the condenser coil still under warranty, paid labor and gas. About the same period of time later, low gas again.

I called someone else - for obvious reasons - and, after using a detector in all accesible places, he suspects the leak is in the wall, possibly caused by baseboard nail (house is modular, sheetrock was already up before A/C, but not the baseboards, chase already builtin to the attic). The strategy is to open the wall in a couple of places around the baseboards (two story house) and take a peak.

I am concerned that the leak may be due to the original installer crap work where he joint the tubbing somewhere in the wall, so I am thinking that after cutting my walls the leak will not be found.

I am thinking about just replacing the run in the wall from where it enters and exits the chase - approximately 25 feet, and skip the time for wall exploring.

Thoughts? Cost of one vs the other, especially if the leak is not found during the first look into the walls?

Regards

 

[ben's plumbing]

Situation: Trane A/C, less than 4 years old, began to loose gas about a year after installation. The company came out one time - could not find the leak topped off system, paid for service. 7 - 8 months later, low gas, changed the condenser coil still under warranty, paid labor and gas. About the same period of time later, low gas again.

I called someone else - for obvious reasons - and, after using a detector in all accesible places, he suspects the leak is in the wall, possibly caused by baseboard nail (house is modular, sheetrock was already up before A/C, but not the baseboards, chase already builtin to the attic). The strategy is to open the wall in a couple of places around the baseboards (two story house) and take a peak.

I am concerned that the leak may be due to the original installer crap work where he joint the tubbing somewhere in the wall, so I am thinking that after cutting my walls the leak will not be found.

I am thinking about just replacing the run in the wall from where it enters and exits the chase - approximately 25 feet, and skip the time for wall exploring.

Thoughts? Cost of one vs the other, especially if the leak is not found during the first look into the walls?

Regards

if it has not been done already.. why not vac out system isolate condenser, coil and test line set before you make any rash decisions....shoulden't take that long for a qualified company to tell if line set is leaking......it should have been done for proper troubleshooting to find trouble from the start...ben sr

 

[carmon]

find and fix the leak......guessing usually costs more money in the long run....

 

[frank otero]

Thanks Ben.

Once it is isolated to the lineset, though, would it be better to start cutting into the wall (two stories worth) to pinpoint the exact leak location to seal it, or would it be better (expense, possibility of a second undiscovered leak) just to run a new line set

 

[COLDIRON]

I agree with Ben, lets see if we can find the leak first before getting to far ahead.
Sometimes it's difficult to isolate the coil from the line sets because there's no valves on them.
Find a good mechanic with a CAN DO attitude that won't quit until the leak is found.
I wouldn't call back the installing Company they don't care about their customers.
If that was my installation it would be my obligation to find and fix that thing for a reasonable cost not continuing to gouge you.
As a matter of fact that kind of thing is a challenge to me to fix and feel good afterward for you and me.

 

[jagans]

one weird thing is that it apparently held pressure for a whole year after installation. Maybe solder used instead of Braze, and vibration cracked solder?

In any event it sounds like all here are correct isolate each component and place under pressure. If each holds, it was a connection.

Alternately, and I leave this up to the HVAC pros. If a leak would cause a change in temperature right at the place where it is leaking, charge unit, run and look at everything at night with an IR camera. If the place where it leaks shows up as hotter or colder then you will be able to see it with IR. You might even see it on the surface of the chase. I can very clearly see where my wall studs are in the winter with IR, Studs are colder than insulation.

Just a thought.

 

[hvaclover]

one weird thing is that it apparently held pressure for a whole year after installation. Maybe solder used instead of Braze, and vibration cracked solder?

In any event it sounds like all here are correct isolate each component and place under pressure. If each holds, it was a connection.

Alternately, and I leave this up to the HVAC pros. If a leak would cause a change in temperature right at the place where it is leaking, charge unit, run and look at everything at night with an IR camera. If the place where it leaks shows up as hotter or colder then you will be able to see it with IR. You might even see it on the surface of the chase. I can very clearly see where my wall studs are in the winter with IR, Studs are colder than insulation.

Just a thought.

A good leak detector in capable hands will always be better.

To detect a temp change a leak would have to pass enough refrigerant to to cause a temp diff. Something that large would be audible..and would leak out quicker..much quicker...than the OP's system.

 

[ben's plumbing]

Thanks Ben.

Once it is isolated to the lineset, though, would it be better to start cutting into the wall (two stories worth) to pinpoint the exact leak location to seal it, or would it be better (expense, possibility of a second undiscovered leak) just to run a new line set

yes if it is for sure the line set ...it may be easier and cheaper to replace it by another route....but you have to be sure its the line set ..if not you will run another line set only to have the same thing going on ...ben sr

 

[ben's plumbing]

Thanks Ben.

Once it is isolated to the lineset, though, would it be better to start cutting into the wall (two stories worth) to pinpoint the exact leak location to seal it, or would it be better (expense, possibility of a second undiscovered leak) just to run a new line set

we don't put fittings into a place we can't get too.they make bending tools for that purpose all fittings are exposed ...ben sr

 

[frank otero]

Very thankful for your replies, gents.

I suspect this leak is quite small since it takes a long time for me to notice the unit is not putting out. In this case, when isolating/pressurizing components, how much time would you need to detect a loss of gas with such small leak?

Merry Christmas

 

[ben's plumbing]

Very thankful for your replies, gents.

I suspect this leak is quite small since it takes a long time for me to notice the unit is not putting out. In this case, when isolating/pressurizing components, how much time would you need to detect a lose of gas with such small leak?

Merry Christmas

we would do a vacuum test on the line set ..isolated from condenser and coil...pending on size of leak..maybe 20 minutes to 1 1/2 hours... hard to tell ..but it will show up if its leaking...ben sr

 

[Hardway]

“why not vac out system isolate condenser, coil.”
Just curious how do you isolate the condenser and the coil?

 

[COLDIRON]

Another way to find stubborn small leaks is to make sure theres refrigerant in the system, then build the pressure up to name plate test pressure with nitrogen then use an approved calibrated leak detector.
You' ll find it.