Air con pipes corrosion

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Air con pipes corrosion

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It's been a few days since I renewed Becky's timing belt and water pump etc. As she's new to us, I've also been working my way through her generally, changing engine oil and filter, checking other filters, etc, etc.

You should see the cabin filter element.

P1070267.JPG

Old one on the left, new on the right! The air filter, bottom, is nearly new which ties in with the service stamps in the book. Engine oil, whilst not "see through" was not that old either. Oil filter was a "WIX" brand - heard of the brand but this is the first I've ever handled - Anyone used them? are they a good make? Wonder if the cabin filter has ever been changed? the cover was very tight to come off - thought I was going to break it!

This morning I was doing a levels check, particularly coolant as the system had been drained when I did the water pump (been checking it every morning and seems to have settled down after the first day) and I was reminded that the air con pipes are showing some surface (actually it's a slight surface pitting) corrosion.

P1070348.JPG

P1070349.JPG

I've seen this before on other vehicles and, when extreme, can lead to failure of the pipe. So I was wondering if anyone has tackled this on their car or knows of a way to stop it going any further and protect the pipes from further attack? I'm guessing it's probably road salt etc that causes it? so it's going to get worse if no intervention is taken.
 
It's been a few days since I renewed Becky's timing belt and water pump etc. As she's new to us, I've also been working my way through her generally, changing engine oil and filter, checking other filters, etc, etc.

You should see the cabin filter element.

View attachment 191396

Old one on the left, new on the right! The air filter, bottom, is nearly new which ties in with the service stamps in the book. Engine oil, whilst not "see through" was not that old either. Oil filter was a "WIX" brand - heard of the brand but this is the first I've ever handled - Anyone used them? are they a good make? Wonder if the cabin filter has ever been changed? the cover was very tight to come off - thought I was going to break it!

This morning I was doing a levels check, particularly coolant as the system had been drained when I did the water pump (been checking it every morning and seems to have settled down after the first day) and I was reminded that the air con pipes are showing some surface (actually it's a slight surface pitting) corrosion.

View attachment 191397

View attachment 191398

I've seen this before on other vehicles and, when extreme, can lead to failure of the pipe. So I was wondering if anyone has tackled this on their car or knows of a way to stop it going any further and protect the pipes from further attack? I'm guessing it's probably road salt etc that causes it? so it's going to get worse if no intervention is taken.


Hi, cabin filter looks like it's the optional activated carbon type (black coloured) rather than just dirty. Best thing for the aircon pipes is a spray or wipe with anti corrosion compound. My favourite is LPS 3 which is designed designed for compatibility with light alloy as well as ferrous metals.



Robert G8RPI
 
The aircon pipe corrosion is generally cosmetic and confined to the low pressure side of the aircon system when the temperature drop causes water in the atmosphere to condense onto the pipes and then subsequently evaporate off.

As g8rpi suggests you can an anti corrosion lubricant. Plenty available. A slight downside is that these "oily" treatments will absorb dirt/dust etc and will require occasionally wiping down and then re-applying.

Another alternative is to lag the low pressure pipes to keep the warm wet air off them.

The pipes are what you can easily see. The heat exchange (hidden) is where massive condensation and cosmetic corrosion takes place. :)
 
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