Furnace not coming on with programmable thermostat

The temperature in my house is 70 degrees.

On the thermostat:

the HEAT-OFF-COOL switch is on the "HEAT" position the FAN switch is on the "AUTO" position

The thermostat's "heat" setpoint is 82 degrees but the furnace doesn't come on for a long time (hours).

When I press the thermostat's UP/DOWN buttons until the temperature reading is 82 degrees, the furnace still doesn't come on for a long time (hours).

What's wrong?

Reply to
home owner
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The temperature in my house is 70 degrees.

On the thermostat:

   the HEAT-OFF-COOL switch is on the "HEAT" position    the FAN switch is on the "AUTO" position

The thermostat's "heat" setpoint is 82 degrees but the furnace doesn't come on for a long time (hours).

When I press the thermostat's UP/DOWN buttons until the temperature reading is 82 degrees, the furnace still doesn't come on for a long time (hours).

What's wrong?

Or should I go back to a manual (non-programmable) thermostat?

Reply to
home owner

No one needs it that warm

70 is comfortable
Reply to
Ed Pawlowski

me on for a long time (hours).

ng is 82 degrees, the furnace still doesn't come on for a long time (hours) .

It would help if you told us the make and model of the thermostat. Does it have a battery? Have the correct ones in there, installed in the right direction? Have it wired up correctly?

The odd part here is that you are implying that it does turn on the furnace hours later, which means it could be a programming thing. But I've never seen a thermostat that would display 82 and with the house at 70, not turn on the furnace, regardless of the programming.

Reply to
trader_4

Totaline P474-1035

The two AA batteries were replaced two weeks ago. They are installed correctly.

There's been no power interruptions, surges or nearby lightning.

Reply to
home owner

Totaline P474-1035

The two AA batteries were replaced and installed correctly two weeks ago.

The red light on the thermostat is on all the time. There's been no power interruptions, surges or nearby lightning.

Reply to
home owner

can you try to bypass the thermostat and see if the problem is with the furnace?

Reply to
Taxed and Spent

Oren

The user manual doesn't say how to set the thermostat back to factory defaults.

Reply to
home owner

You imply it has been working until now. You can usually bypass the T-stat just by putting the two wires together. You may have a bad gas valve, flame sensor, ignitor, etc.

Reply to
Ed Pawlowski

What position is the Program switch on the side of the thermostat?

Reply to
Idlehands

He implies that now, but from the first post:

"Or should I go back to a manual (non-programmable) thermostat? "

It sounded to me more like he just put it in. Again, that's the problem with these post, little info, no make, model, nothing.

But I agree, if it were mine, I'd directly connect the wires for heat and see if the furnace comes on, because it could be a problem with the furnace, bad connection, etc.

Reply to
trader_4

To Trader4 re: "little info, no make, model, nothing":

23 hours ago (at 12:09 PM on 1/18/2017, I said I have a Totaline P474-1035.

The thermostat was installed about 5 years ago but the problem developed in the past year.

Reply to
home owner

Does it have a battery? Has it been replaced? Sometimes it shows the display but does not have enough power to trip the function called for.

Reply to
Ed Pawlowski

I am wondering about that too, also whether he is grasping the concept of a span, that many thermostats have built in.

Reply to
FrozenNorth

Yes, the thermostat has 2 AA batteries. I replaced both batteries a week ago (and Yes, they are installed correctly)

What do you mean by "span"? Does my Totaline P474-1035 have a built-in "span"?

Reply to
home owner

Have you tried what several of us have suggested? Find the 24V power wire and "heat" wire coming into the thermostat, connect them together, see if it starts? I gave you the colors typically used in another post, it's usually red for power, white for heat.

Reply to
trader_4

trader_4: What do you mean by "span"?

Reply to
home owner

FrozenNorth: What do you mean by "span"?

Reply to
home owner

Your Totaline calls it "dead span". See page 17 of user manual at:

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This explanation is quoted from

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"The span setting regulates when and how long your system will run. The span has been set at the factory to 2 which will allow the system to turn on 1 deg.F(.05 deg. C) above or below the set temperature and run for 1 deg.F (.05 deg.C) above or below the set temperature. If your thermostat is set to turn on at 72 in heat mode, with a span setting of 2, your thermostat will activate your furnace at 71 and shut it down when it reaches 73. For cooling at 72 with a span of 2, your air conditioner will activate at 73 and shut down at 71. This setting can be changed to 1, 2, or 3. 1 will shorten your running time while 3 will lengthen it."

The issue is the actual turn on & turn off temps should never be equal. Should be at least 1 deg different, and usually 2 or 3. Some times also referred to as "hysteresis".

With room temp of 70, and set temp of 82, this is not likely to be your problem. Most likely it has died of old age, or maybe there is a wiring problem between it and the furnace. That's why others have said to short together the white and red wires and see if furnace starts, or not.

*ALSO*, I just stumbled across the "Factory Reset" instructions at:
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"Factory Reset: Move Program switch to Set, hold Next to enter setup, press Next to go to step 2 (?Cy?), press and hold Next until all icons appear, press and hold Next until ?Fd? appears. Press Next three times, then move Program switch. "

Good luck.......

Reply to
Retired

It is a setting on my Honeywell thermostat, it adjusts between electric, vs natural gas etc and the time they take to heat and recover. If you set your thermostat, for 72 degrees, it may not urn on till it gets to 71.5 and be off at 72.5 as an example at one setting, but could be even closer or looser on other settings or the type of fuel.

Note I just pulled those numbers out of my ass, the idea is to keep your furnace spending all day shutting on and off.

Reply to
FrozenNorth

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