Is a New Lineset Necessary When Replacing an Air Conditioner?

We provided a quote for a new air conditioner recently and the customer asked this:  "All I want is a new air conditioner.  What is a lineset and why did you quote that?"

That's a great question!  First, the lineset is what carries the refrigerant from the coil in the air conditioner to the coil in the furnace.  Now, why would we quote a new lineset with the new air conditioner?

You may have heard that there are two types of refrigerant.  If you have an older air conditioner, it likely uses R-22 refrigerant.  New air conditioners use R-410 refrigerant.  R-22 is being phased out by the EPA because there is chlorine in it which contributes to ozone depletion if it leaks out of the system.  Eventually, all air conditioners and heat pumps will use R-410 refrigerant.  R-410 is an ozone friendly refrigerant.

These two types of refrigerant contain different oils and do not mix well.  R-22 contains mineral oil which doesn't mix well with POE oil, which is in R410.  Therefore, running R410 refrigerant through a lineset that once carried R22 refrigerant will eventually be detrimental to the system.  It will ultimately shorten the life span of the compressor.    Ideally, the best option is to run a new lineset so there's no chance of the two different oils mixing.  If a new lineset is not an option for whatever reason, a flush can also be done.  This is a chemical used to flush out the R-22 that ran through the lineset.  It is effective, however, it's not likely that 100% of the oil will be flushed out.  Therefore, we recommend a new, clean lineset when possible.

During the quoting process, the technician will look at the placement of the current lineset to determine if a new lineset can be run.  There may be some measures that have to be taken, such as a new bulkhead, to install a new lineset.  In the end, this is still important to consider the lineset to ensure that your new system is running top-notch for years to come.

Feel free to contact us if you have any questions about the two types of refrigerant, the phasing out of R-22 or linesets!