Thermostat wire?

anthony_7

I am doing and addition with three new zones. Question is it ok to run 18/2 for the t-stats or should I go 18/3 or more... I also will be running two zones for central a/c down the road. Although the handlers will be up in the attic. Thanks

Unknown

I'd run 5 conductor

In the event there are two scources of 24 volts, you would need a Rc; Rh; W; Y; and G. The two R wires are for the two different scources, one for cooling and one for heating. Y is cooling on, G is fan on, and W is heat on.

Noel

Dale

Noel right

Never less than 5 conductor as the better stats need a common to keep the clock batt charged, 18 gauge has reasonable voltage drop for a NEMA 24V tfmr.

Jack Smith

18/8

I run everything in 18/8. rc,rh,w1,y1,g,com,w2,y2. Besides what happens if you get a break in the wire. Have had it happen, thank God for the extra conductors!

hot_rod

Wire's cheap

run some spares. If the unit requires 4 or 5 conductor consider running a second 5 conductor so your spares are in a seperate wire. Often when a nail, or whatever hits a wire you lose more than one conductor. The second cable is cheap insurance. Extra conductors give you upgrade ability should you add outdoor temperature monitoring or something.

I like to run my wires to a plastic electrical box so there is room to store the spare and allow ease of wiring for the stat. It also provides a better mounting than just sheetrock! Make sure the stat you use will cover the box and is in the right position!

hot rod

To Learn More About This Contractor, Click Here to Visit Their Ad in "Find A Contractor"

jim f

i also run 18-8 to all thermostats even if they only need 2. i also run 18-5 to all condensers to accomadate sensors and any thing else the new products of the industry have to offer
jim f.

Boilerpro_3

Stats are becoming obselete.....

I'd run shielded cable to provide the ability to use Room temp sensors without the potential of interference.

Boilerpro

Unknown

Outstanding idea

Interference on low voltage wires to electronic controls are amoung the hardest to troubleshoot, to isolate to an area, and to remove and replace.

It's so easy to prevent it, as you said.

Noel

BillW@honeywell

Good advice!

18 gauge wire is the choice for our thermostats, and I usually recommend the 5 conductor wire, too. Excellent point about the shielded wire, especially for sensors that are used with our T8600 and PC8900 series. Hot Rod's idea of using a Jbox and running a spare is also good, but just make sure the box is insulated to avoid sensing wall cavity temperature. Something so simple, yet so important. Another point is what transformer you use...the few pennies you save by installing a non-NEMA transformer is quickly lost in callbacks & customer dissatisfaction. Most non-NEMA transformers produce either low or erratic voltages, murder on electronic stats, fan boards and boiler controls.