Question regarding a "kink" in a home central air conditioning line

[John2004]

Hello,

HVAC is not my area of expertise. I would like to ask a few questions regarding a home central air conditioning unit.

My parents just had a new home central air conditioning unit installed (Westinghouse). During installation, one of the new copper AC lines was kinked "very bad" (practically folded over 180 degrees at one point, and bent 90 degrees at another point).

I think it was the larger insulated line that was kinked, and not the smaller un-insulated line.

Depending on which line was kinked, what kinds of problems can this cause ? Should this be fixed before they start using the AC unit ?

The company my parents hired kinked the lines, but did not tell my parents about it. It has only been a few days since the installation, but the company has been paid.

I would think this kink would restrict flow, increase pressure, and possibly shorten compressor life or decrease cooling efficiency. However, as I said before HVAC is not my area of expertise.

I would be grateful for any feedback and advice.

Thanks for your help.

John

 

[MintJulep]

John,

You've pretty much got it figured out.

Get the lines replaced.

 

[John2004]

Hi Mintjulep,

Thanks for your reply.

I would prefer to replace the whole line, however the lines are in a very cramped crawlspace. Also, before the lines get to the furnace / evaporator, they go through a wall, and have a very tight fit with other lines, i.e., heating vents, drain pipes, water pipes, etc..

It looks like a tough job, and I don't know if the HVAC guy will give me any problems in re-doing the work.

Is it possible, (or more importantly acceptable) to cut the kinked portion out of the line, and solder in some type of coupling ? Is a compression fitting acceptable ?

I am asking this, as I anticipate that the guy that did the work may suggest something like this.

Thanks for your help.

John

 

[cme]

The larger insulated line is the suction line and the smaller non-insulated is the liquid line.

The piping has to be Type ACR and joints brazed.

Compression fittings are a no-no.

Typically on those residential units, the piping is either quick-coupled or they use flared joints. The tend to be a source of leaks and fail just when its a design day. I don't allow that in my specs and make them conform to commercial standards.

 

[MintJulep]

John,

You can count on the HVAC guy giving you problems. Have your lawyer's phone on speed dial.

Yes, it would be possible to cut out the damaged sections and braze in a new section. But now you have four brazed joints that are potential future leaks where you should have none.

There are compression fittings that would be suitable for refrigeration service. They are expensive. They are not available at Home Depot. They will not work on soft annealed pipe that it sounds like was used.

You paid for a continuous, undamaged suction line between evaporator and condenser. That is what you should get.

 

[John2004]

Hi everyone,

I just wanted to say thanks for all the feedback. Hopefully, I can help my parents to get this worked out, and get the HVAC guy to do the right thing.

Sincerely,
John