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Running control cable with Liquid Refrigerant Line

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Good Day folks,

Search for this but did not find any hits. Would there be any reason I could not run my 18ga control cable through the same foundation penetration as the insulated heat pump liquid refrigerant line?

The house is a high performance dwelling and all penetrations are air sealed on outside. The foundation is insulated on outside surface.

I did not allow for enough penetrations, so I would have to dig out gravel, strip dimple membrane and insulation off and then drill and seal the new penetration if I can not run cable with liquid line (cant use suction line hole as just big enough for insulated pipe).

FYI, the line-sets immediately exit below grade (and are well insulated against foundation where below grade - aprox 12") and will be run against wall not buried in case someone was going to yell at me for burying it :-)

Many Thanks for your insight
Sean Wiens

Comments

  • Ironman
    Ironman Member Posts: 7,378
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    Just make sure it doesn’t get chafed.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
    SENWiEco
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,607
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    Not the greatest. I mean what kind of cable can you run underground that is suitable for direct burial?

    I would prefer to see a whip of non metallic seal tight run from the condensing unit to the interior of the house.

    I know it's standard practice to run regular thermostat wire from the condensing unit to the house exposed outside and it's done all the time but

    That stat cable I am sure is not listed for burial, outdoors exposed and has no UV protection
    SENWiEco
  • SENWiEco
    SENWiEco Member Posts: 159
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    Thanks @Ironman - yes will protect. Was worried there would be a temperature reason not to do this. Sounds like I am good

    @EBEBRATT-Ed - I will be running the line sets through a PVC cover channel and would run the 18ga HVAC cable along with the liquid line (strapped to outside of insulation). Other than exit from foundation, this cover/channel would all be above grade mounted to wall. The part below grade is only 6" and the surrounding fill around the PVC cover/channel is very well drained gravel.
    Sean Wiens
  • HVACNUT
    HVACNUT Member Posts: 5,858
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    Its common practice to run the control wiring with the line set. If its A/C only, run 8 conductor. If its a heat pump, run two sets of 8 conductor. One being a spare. Things happen over time and it's nice to have extra wires if there's ever a short, or open circuit, or a critter snacked on it.
    SENWiEco
  • SENWiEco
    SENWiEco Member Posts: 159
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    thanks @HVACNUT - will do.
    Sean Wiens
  • pecmsg
    pecmsg Member Posts: 4,881
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    How much line set runs underground?
  • SENWiEco
    SENWiEco Member Posts: 159
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    @pecmsg only 6"-7"
    Sean Wiens
  • JUGHNE
    JUGHNE Member Posts: 11,074
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    Where we have had to enter a building below grade for utilities, we would put a sturdy window well at that point. Make the bottom of gravel/rock to drain.
    This removes the penetrations from "being below grade", makes them accessible and obvious to any future grade work.
    SENWiEco
  • SENWiEco
    SENWiEco Member Posts: 159
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    Thanks @JUGHNE I am planning on similar. I have the gravel covered, that side of the house is backfilled with gravel so all the way from grade down to the footings 12ft below. I plan on a 10" piece of PVC cut in half to create the access 'well' once the concrete sidewalk is poured in area.
    Sean Wiens
  • JUGHNE
    JUGHNE Member Posts: 11,074
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    IMO, half of a 10" pipe seems small.
    Consider having to change the large suction line, it would require a brazed 90 fitting where it exits the wall below grade. Perhaps there is one there now.

    I am thinking of 1/2 of perhaps a 16" round galv metal culvert. This would be scraps to a street dept.
    In any event I think you would want this to extend up a couple inches above the sidewalk.
    You would want a finished edge at the top.

    There are also some 1/2 circles of fiberglass that are used in septic drain fields. IDK the correct name of them. Someone here may know what I mean.
    SENWiEco