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My Frankenstein HVAC

Benjamin_Katydid | Posted in General Questions on

We’ve had a few HVAC contractors out to quote an overhaul of our central AC system. I would love to go all ductless but there doesn’t seem to be anyone around who building sciences. So the current plan is to minisplit two areas on the extreme ends of the house and downsize our central unit for the rest of the house. That’s not ideal but it’s better than the current state.

One item which we’ve received split opinions on is the copper line to the central system. A previous owner needed to have the line replaced for whatever reason and the contractor routed the replacement line all the way around the house inside a metal shroud. One contractor told us it was a problem. Another said no not really but maybe because there’s an ‘oil trap.’ And two more said no problem. Is there any value to removing this line and rerouting it straight through the house to the attic–which was the original route? Rerouting will cost $800 and will tear up sheetrock in a bathroom, so we are wondering whether we’ll see that much ($1500?) benefit from fixing something that may or may not be broken.

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  1. Expert Member
    Dana Dorsett | | #1

    I'd personally be reluctant to re-use an old refrigerant line independently of how it was routed, even if it's using the same type of refrigerant. It's too iffy.

  2. Benjamin_Katydid | | #2

    Thanks Dana. Now would definitely be the time to replace it then.

  3. Expert Member
    AKOS TOTH | | #3

    Before dumping big $$ on fixing your existing HVAC, you have to figure out if the unit in the attic makes sense.

    Usually this is a bad idea in all climates and is costing you real money in terms of operating cost. It also means you need to oversize the unit because of the additional losses, adding further to an upgrade costs.

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