I often see air conditioner installs that appear to have no t-stat line going to the remote condensing unit. This can be for three reasons: - it is run within the power conduit (a violation); - the unit operated on the principle of 'pressure drop,' and needs none; or, - as shown here, the HVAC guy ran the wires with his 'line set.'
These pics show the need to know a little about other trades, as well as your own.
John, I used to work for a company here that specialised in installing AirCon/HVAC equipment and the majority of our systems worked off of a Pressure switch. Running a thermostat wire inside the same conduit as the Mains wiring sounds a little dangerous, considering that the T/Stat wire is often very lightly insulated, to say the least. Speaking of insulation, were these pictures taken before the HVAC guy had a chance to insulate his pipe-work?. Often the liquid (smaller) line would go un-insulated here. I was hooking up the power to a new house recently where the Building Inspector refused to sign-off the Building Completion Notice until there was insulation on the Gas (larger) pipe of the AC system. Un-insulated pipes like this cause water problems from dripping Condensation.
One must start the day early to slip one past Trumpy!
Yes, I took the pic before the insulation was added, so you could see the wire.
NEC does ban running "power limited" circuits in the same raceway as power cables- so running the t-stat wire together with the power leads is a violation. The whole point of my pic is to show your average non-HVAC person that the t-stat wires are often run separate from the power, even though they may not be visible without taking things apart.
Likewise, most electricians are not aware that some systems don't even have a cable run to the condenser (outside unit).
Re: HVAC T-Stat Wire Routing#120785 05/05/0504:10 AM05/05/0504:10 AM
BTW John, Who was that idiot that nailed that dwang (Horizontal timber piece) in to hold the T-stat wire, in the top pic?. Looks like the nail-gun completely missed as did the person fitting the dwang.