Lineset Leaks

> @EBEBRATT-Ed said:
> I just see those systems being a nightmare. Time will tell........it always does

Yeah but hindsight is useless.

Good Afternoon all, I just wanted to chime in for a minute. My name is Rick and i work with as a manufacturers rep in which we rep a manufacturer that produces the white insulated line sets. I have seen many cases of corroded line sets from every manufacturer (mostly because guys assume that all white line set is the same when in fact there are many different manufacturers). We also had concerns as a rep firm and had some of the leaking pipe tested at a lab to check copper quality as well as the possibility of the insulation reacting with the copper. We were happy to see that the copper quality was far better than the standard for ACR copper as well as no traces of chemical properties of the insulation on the copper. What we did learn is this is no different than what is happening with a/c coils. This is known as formicary corrosion or "ants nest" corrosion, this happens when you have copper, water, oxygen and an organic acid (ex. salt and many other airborne contaminants). Everyone always asks "how come we didn't have this problem before?" and what i try to explain is when we ran line sets with armorflex or kflex insulation and it was exposed to uv the insulation would break down and the moisture on the pipe had no place to get trapped. This was obviously not efficient for the equipment so going to white line set insulation which holds up better to uv when treated properly and better R-value made the system more efficient but if we are in an environment where we have high humidity the pipe will still sweat and the water will now get trapped in the insulation. That and with the addition to salt in the air especially near the shore you make the perfect storm for formicary corrosion and the copper will deteriorate in no time. I am not sure what other manufacturers are doing to combat this but i know we went back to ours and worked very hard to come up with a product that we believe will hold up and stop this from happening. Anyone looking for more info on this topic i would be more than happy to continue the conversation. Send me a message and I'll give you my contact info.

@hvac,
Im having trouble reconciling some things with what you've stated as the cause of the linesets leaking.

First, you state that the old linesets with Armorflex didn't leak because UV rays broke it down and it couldn't hold moisture. How do you explain the thousands of feet of linesets that I've installed or come across that weren't exposed to UV because they were inside or covered? If what you're stating is correct, then all of them should have been exposed to formicary corrosion just like the white ones because they would have held in moisture.

Second, you blame salt in the air getting through the white insulation even though water can't get out. Is this to be understood as the same as O2 diffusion with non-barrier PEX? Salt can get in but moisture can't get out? I think you'll find this problem exists in areas far from the coast that don't salt their roads because of their warmer climate.

I'm not sure what the cause really is, but after 48+ years in this trade I can tell you that it didn't happen until the white Asian linesets came along. I can also tell you that most of the ones that I've used have inferior copper that kinks more easily - even in a bender.

@ChrisJ,

I'm not sure if we've used any. We basically have two or three supply houses that we get linesets from and they keep using whichever vendor is the cheapest that month.

So I have had over 25 coils in the last 5 or so years leak.

All were replacement systems in existing houses, most of the houses were 50 years of age or older. The vast majority of the equipment being replaced was 20 years old, or older. Some were 30 years old.

The Homeowners were the same Homeowners of the coils that lasted 20 to 30 years. It was the same air in the house, the same cleaning products in the house. The same carpets, rugs, furniture. The same off gassing , on and on.

Except the new coils lasted less than 5 years.

Therefore, I call baloney about your formicary corrosion excuse, along with all of the other excuses I’ve heard.

And I’ve heard excuse after excuse.

The coil manufacturers used and made cheap junk.

The installer and the contractor are the ones that are suffering and paying for it.

I can’t wait until it happens to some lawyer, and he decides to file a class action lawsuit.

At least he’ll get rich off of it, and the coil manufacturers will have to pay.

I suspect it was just the cost of copper skyrocketing.

How many of these old coils that were replaced after 30 years were replaced because the coil itself leaked?

The OP had mentioned coils in his original post.

The linesets have the same problem as the coils do.

realliveplumber said:

I can’t wait until it happens to some lawyer, and he decides to file a class action lawsuit.

At least he’ll get rich off of it, and the coil manufacturers will have to pay.

The manufactures are going to shift the blame to the feds for there stricter energy requirements.

A larger coil uses more tubing so in order to pay the same for the metal, you have to stretch it thinner. There is a little bit of an argument that thinner metal transfers heat better but I suspect that is negligible compared to increasing the overall surface area of the coil.

Solid_Fuel_Man said:

I think, like most things, it comes down to price.



Copper is expensive, so the manufacturers use it as sparingly as possible. They have figured out how thick the copper must be to satisfy their design pressures with a decided margin of error.



We also have to remember that old R22 ran at lower pressures, and was generally in thicker copper coils etc.



I also wonder if the quality (purity or alloy) of copper has more to do with it. Most of the copper we are using has likely been recycled at least 5 times now. 30 years ago, it may have been through the furnace 3 times, I dont know.



Think of the old R12 days, when we could use rubber hoses and clamps for refrigeration!

Why do you think any of the copper used in refrigeration has been recycled at all? Have you seen a manufacturer claim this?

> @mattmia2 said:
> If it is freshly smelted from ore or melted down scrap probably has little to do with quality (other than assorted other metals alloyed in), how well you remove slag and separate oxides when you process it probably has a lot more to do with quality.

I have a feeling metal is like water and can be recycled forever.

I'm just curious why @Solid_Fuel_Man felt they were using recycled copper.

The recycled copper and brass we sell goes somewhere. It probably can't all go to China.
The quality control of reusing it probably varies greatly.

As far as thinner copper coils, maybe milk a little more heat transfer to raise the SEER. And to milk a little more profit.

I think it is all involved in the race to the bottom.

Now that they've been out there a while, has anyone seen the Rheem aluminum coils leak?

I never heard that. Am.Std./Trane is sending aluminum replacement coils where you have to re-use the drain pans and the TXV from the old coil.

No more white lines for us. I’ve bought 6500 feet of black stuff so far, and just ordered another 3280’ this morning. #savedoughbuybulk

Read 3.7

The cases coils don’t have the sheet metal shields. I tear out the old foil lined insulation and use the new insulation from the new cased coil if we don’t change the casing.

I'm unaware, what is the issue? The aluminum can't touch the skinny insulation in the cabinet, if the copper touched it?

Solid_Fuel_Man said:

I'm still curious if it's the wall thickness, or the quality of the copper.



As to my recycled comment, it's my understanding that pretty much all copper, steel, iron, etc. are recycled in mass quantities. And most of it goes to China, where, as we all know, when it comes back some is good quality and some not so much.



In the electrical industry, copper conductors, must meet a purity standard to be sold as copper conductors. I'm just questioning what standards manufacturers have for coils/line sets. I'm sure @hot_rod can tell us that raw material quality control is something manufacturers have to keep a close eye on.

I'm curious what they use as well but I highly doubt anyone would say.

Mueller says right on their website what they use for their linesets I believe.

I wonder if the actual issue is that the copper connected to the aluminum, the steel of the furnace and ductwork, and the condensate are setting up a battery that is dissolving the aluminum tubing. I can see where the facing of the insulation or residue on it could be part of the circuit as well.

That page that @realliveplumber posted above said the problem is galvanic corrosion between the copper and aluminum. I suppose it wouldn't take much to cause a pinhole in Al, esp. if the copper isn't eroded at the same rate.