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gba
Dec 4, 2007, 07:43 AM
My furnace never reaches the target temperature on the thermostat. Even if I increase the temp on the thermostat, the temperature is never met. The current temp is set for 74 degrees, it was 62 this morning? The furnace is a Goodman, the thermostat is digital. I just replaced the thermostat because I thought the old one didn't work. Nothing changed. When I connected the new thermostat, there were several colored wires. I connected all wires, including a red wire into the Rh slot. The Rh/Rc slot had a jumper. Should I have removed the jumper?

hvac1000
Dec 4, 2007, 10:52 AM
Leave jumper alone.
You have another problem besides a thermostat.
Are your air filters clean?
Does the blower motor run?
Is the burner cycling on and off rapidly?

gba
Dec 4, 2007, 11:31 AM
I just replaced the air filter, is there any others that need to be replaced? The blower motor seems to be running, and the cycle isn't real rapid on/off, it lasts about 15 minutes before shutting off

hvac1000
Dec 4, 2007, 01:06 PM
No other filters that I know of. I guess all of your registers are open?
Thermostats can have adjustable heat anticipator settings. Look in your install manual to see if there is a section on it listed. You might have to increase that setting.
Has this furnace worked well before or did you just buy the house?

gba
Dec 4, 2007, 01:48 PM
Its pretty much always done this, I decided to change the thermostat because it was old and falling off its mounting. I assume all the regesters are open? Is there a certain place I should make sure if the regesters are all open? Air does flow into all the rooms, its just a question of shutting off before the target temp is met? Is there a heat anticipator setting even on digital/programmable thermostats? I don't recall seeing anything in the instructions. Do you think that maybe its restricted ductwork? Any way to fix that?

hvac1000
Dec 4, 2007, 01:53 PM
Usually there is a way to change the heat anticipator setting. What is the brand and model number.

gba
Dec 4, 2007, 02:02 PM
It's a honeywell, I don't have the model number with me... could it be possible that something on the furnace itself can be adjusted to increase its cycle time?

hvac1000
Dec 4, 2007, 02:12 PM
NO it is adjusted on the thermostat. I will need the complete model number.

Another possibility is a limit control that has lost it setting/or went out of calibration. Usually these are not adjustable on many furnaces and have to be replaced.

gba
Dec 4, 2007, 02:23 PM
I can get the model number in an hour...

As for the limit control, where is it located and is it possible for me to fix it or even know if its lost its setting?

By the way, you've been a great help... thank you very much...

gba
Dec 4, 2007, 03:31 PM
The model number of the thermostat is honeywell RTH221

MEGH2010
Mar 15, 2008, 09:07 PM
NO it is adjusted on the thermostat. I will need the complete model number.

Another possibility is a limit control that has lost it setting/or went out of calibration. Usually these are not adjustable on many furnaces and have to be replaced.

Is the "limit control" on the heater or the thermostat?

Thanks, Meg

MEGH2010
Mar 15, 2008, 09:15 PM
No other filters that I know of. I guess all of your registers are open?
Thermostats can have adjustable heat anticipator settings. Look in your install manual to see if there is a section on it listed. You might have to increase that setting.
Has this furnace worked well before or did you just buy the house?

If the "heat anticipator" was set too low, would you be able to just increase the thermostat setting? Or, would this require that the thermostat be turned off to "reset" and turned back on to a higher temp? Thanks, Meg

hvac1000
Mar 15, 2008, 09:46 PM
See configuration menu 3 on the link below

http://customer.honeywell.com/techlit/pdf/69-0000s/69-2060EFS.pdf



Heating cycles
Per hour

• 1: 60 min (steam, gravity)
• 3: 20 min (hot water, 90%+
High-efficiency furnace)
• 5: 12 min (gas or oil)
• 9: 6.7 min (electric

Make sure it is still set to 5 for 5 12 minure cycles per hour.

One other thing you mentioned in on of your posts.

(((Its pretty much always done this, I decided to change the thermostat because it was old and falling off its mounting. I assume all the regesters are open? Is there a certain place I should make sure if the regesters are all open? Air does flow into all the rooms, its just a question of shutting off before the target temp is met? Is there a heat anticipator setting even on digital/programmable thermostats? I don't recall seeing anything in the instructions. Do you think that maybe its restricted ductwork? Any way to fix that?)))

You said it has pretty much done this. So this problem was there before the new thermostat?

There has to be a reason the furnace is turning off before it meets the temperature requirements you set on the thermostat.

The thermostat controls the call for heat but other items like a defective high limit control, or other controls in the furnace can cause this to happen. I believe your furnace needs to be looked at by a professional especially since this has been doing this for sometime. With out specific meter readings and being able to be there to test it is all guess work here.