Warm air furnace

trip main breaker in breaker panel, open up furnace and open small door at bottom to access electrical wiring. most of the time on older furnaces , fuse is in series with low voltage red wire..

1) You got a FIRE truck coming.

2) Wire is too small.
Problem is NOT circuit breaker.

3) Both 240Volt appliances on same breaker is a hazard, especially if space available in 200 amp service panel for more breakers.

4) Usually each 240V appliance has separate breaker.

5) Circuit breaker trips because of High heat on the wire.
If wire gets hot, it will start a fire inside the wall.

Electric code requires wire-size match breaker-size.

6) If you put larger amp breaker on same wire that is getting hot, then wire will get hotter.
Result: FIRE truck middle of night with folks jumping out window in glass-cut bare run across yard.

7) Each appliance has volts and watt rating on label.
EVERY appliance has label.

8) For example stove might be rated 8000 watts and 240Volt.
8000 watts divided by 240 volts = 33.3 amps
Stove would require 40 amp breaker and 8 gauge wire.

9) How to figure it out:
http://waterheatertimer.org/Color-codewire.html
http://waterheatertimer.org/How-to-install-a-subpanel.html

10) Do same calculation for new furnace.
12000 watt furnace divided by 240 volts = 50 amps.
Use 60 amp breaker and 6 gauge wire.

11) Summary: fixya wants you to be safe, and buy stuff showing in the ads.
Use a bigger breaker ONLY when bigger wire is also installed.
Call furnace installer, the installer should know to check safe wiring before installing.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

I don't know where you live, so I don't know if there is a color code used like there is here, in Massachusetts. Typically, white is neutral. Neutral and ground are not really interchangeable terms to electricians - but often are to homeowners. Read this until you understand:

1) If you have two separate bars in your panel, and one has only white and / or gray insulated wires connected and the other has only bare or green or green and yellow striped insulated wires connected, you must connect the white wire to the bar with the white / gray wires. Do NOT connect it to the bar with bare / green insulated wires.

2) If you have one or more bars in the panel, and both have a mixture of white / gray and bare / green wires, and the bars are screwed directly into the panel back - or have a jumper connected between them, you should be able to connect the white wire to any available terminal on the bar(s).

Colored insulated wire (not green, white or gray) usually means it is not neutral or ground. In an electrical panel, most times if it is not neutral or ground, it is "hot". If there are two colored (hot) wires and a single white or gray (neutral), the white goes to neutral bar and the hot wires go on adjacent circuit breaker terminals - in this case, a 2 pole circuit breaker.

Your gas or oil fired furnace likely operates on 120 volts (hence the white wire for neutral), while the AC compressor and blower is probably 240 volts (hence the need for the second colored wire). You may need to connect these two hots to one "2 pole circuit breaker" for the AC to work.



A typical 2 pole circuit breaker has two handles tied together - and internal connections.

Look at the wires to get an idea as two what size breaker they need to be connect to - #8 copper 40 amps, #10 copper 30 amps, #12 copper to 20 amps and finally, #14 copper to 15 amps. If you are unsure, and my background on the way things should normally be do not jog your memory, STOP. call an electrician and have it connected correctly and safely.

Disconnect the black power wire where it is connected to the furnace with breaker off. Put a wire nut on it and then turn the breaker on. If it continues to trip, the problem is not the furnace and you will have to trace the power wire back to the breaker box to find problem. Next, disconnect the black wire from the breaker (with breaker off) and then snap breaker on. If it trips, bad breaker. If the furnace was disconnected and breaker did not trip, you have a short either on the P C Board or the transformer.

When does it trip? Do the burners light first? How many minutes from "ON" to trip?

Hello, Typically your common wire will be white, high speed- black, medium speed- yellow, medium low-blue, red- low. The motor could still run for a short time if it was wired wrong but will either trip a breaker or go off on it;s overload when it's gets hot.

Look at rating plate on motor.
Look for volts, watts, amps.
Figure with Volts x Amps = Watts.
Amps = Watts divided by Volts
1 hp horsepower is 756 Watts.

Lets say you have 120Volt 2hp motor
So 2 horsepower motor draws 1500 Watts
Amps = 1500 Watts divided by 120Volts = 12.5 amps = so you need 120Volt 15 amp breaker with at least 14gauge wire (as long as motor is located within 50 feet of breaker.)
If motor is farther away, then you need 20 amp breaker with 12gauge wire.

Look at circuit breaker rating.
If motor is 240 and breaker is 120, then it will trip breaker.
If motor is 120 and breaker is 240, then it will trip breaker.
If breaker is for 15 amps and motor draws 20 amps then it will trip breaker.

Generally speaking, if motor and breaker are 120V, then black wire goes to black wire; white wire goes to white wire and green wire connects to bare copper wire.
If motor and breaker are 240V, then wire colors can be different. Black-red or Black-white from breaker connect to Black-red or Black-white at motor.

Add a comment. Say the motor rating and color of motor wires. Say the breaker size and color of wires coming from breaker and I will help you wire the device.

The red and black wires if ran correctly are the load lines(power). The white is neutral or ground. If its a 1/2 to1-1/2 hp motor connect the red and black wires to terminals #1 and #4. If its 2 hp use #1 and #4. If its 3 hp use #2 and #4. Connect the white wire to the green colored screw. A grounding conductor should always be connected under the green grounding screw, which is located within the terminal compartment of the motor. You can check the breaker for the wire colors, one should be black and the other red. The white wire should be terminated to the neutral/ground bar in the can.

I can give you a start, For heat only, R terminal on furnace to Red wire to R or RH terminal on thermostat. W terminal to White wire to W terminal on thermostat. G terminal to Green wire to G terminal on thermostat. This will get you heat but not air conditioning.

fuse is usually a small resetable breaker on the side of the transformer, or a traditional screwin fuse with a plastic cap on one end that is a specialty fuse and is available at most motor shops or elec supply houses. or its a auto type plug in fuse on the circuit board usually 5 amps or three amps. first turn the fan switch on the stat from auto to on. does fan run? if it does you have high and low voltage and your wired wrong. if it is in the stat you are usually looking at red connects to red . yellow to yellow, green to green , orange to orange, white usually to white, that leaves a common power wire to operate the stat, usually connected to the common term on the new stat . this can be any color and is necessary for the new stat to think and work, if it has batteries it will have a display but it needs a red and a common to think and work. this wire can be any color and if your old stat had no common which a lot didnt then youll have to add one. carrier also has a emergency heat strip wire sometimes labeled x2 etc. you can usually jump white over to x2 to perform function if needed. good luck.