HVAC wiring question

[coach]

Are there any particular requirements for low voltage wiring connections for thermostats? I see all sorts. Wire nutted, taped and wire nutted then taped.

 

[427mach1]

Not sure about any code or requirements but as an extra precaution I always use wire nuts and tape just to be sure nothing can get inside the nut and short it out. I don't like electrical leaks.

 

[NikA]

I just worked on mine last week. They were sheathed together in a bundle directly from the thermostat to the furnace. I wouldn't want to run individual strands for this job, and the wire is small enough that I can't see splicing it except for an expedient temporary fix. Connections at both end just attach to screw terminals.

 

[coach]

I’ve seen a lot of furnaces/air conditioners and haven’t noticed home runs before, but all were old houses with replacement systems. Wire nutting the connections and taping seem prudent. I’ve seen a lot of sloppy work at times including twisted wire that lost the wire nut or never had one and wire touching a metal flue pipe with melted insulation. I’ve never seen a junction box used like done with line voltage wire splices. The connections I see are near the furnace.

 

[blume357]

It's usually pretty poorly done around here.... I'd do my best to run one group of wires and not splice and also keep it tight and secured and don't leave wires hanging in crawl spaces, basement or attic where folks can get tangled up and pull on it.

 

[wwb]

If there is any slack available, pull in an inch or two, strip 1/2 inch or so from each wire, slide a piece of heat-shrink tubing over one wire, and solder the two wires together (rosin core solder or rosin flux - no acid flux). Slide the heat-shrink tube over the joint and shrink it.

This is NOT code with 120 volt wiring, but is just fine with t-stat wiring.

 

[Jimbo357mag]

Wire nuts are fine for low voltage but they should be contained in an electrical box of some kind or behind a panel.