heating trouble

[COMFORTHVAC]

i have a 48tme012 and the only way that I get the heating call to work is to turn the IDF to on,then eveything will run IDF and burners come on and will cycle on the therm for temp. If fan left in auto the unit will not do anything. I disconected the therm wires at unit and jumped out r-w1 no action but r-w1 and g unit starts. The ignitor module and limin switch were replaced July,2012

[flanders]

I'm not sure about that unit in particular, but some units must have a G call with W for the furnace to come on.

[timebuilder]

What are the first five digits of the serial number?

[COMFORTHVAC]

What are the first five digits of the serial number?

5105G30610

[Eadam1985]

is there a time delay relay in the unit?

[Dallas Duster]

The unit should start in heat mode with a closure for R to W1. We're there any alarm codes blinking on the igc? Is there a basic stat on it or any other controls?

[timebuilder]

The unit should start in heat mode with a closure for R to W1. We're there any alarm codes blinking on the igc? Is there a basic stat on it or any other controls?

I agree. Power to W1 should start the inducer, and the fan will come on after a time out expires.

You have something amiss here.

[timebuilder]

i have a 48tme012 and the only way that I get the heating call to work is to turn the IDF to on,then eveything will run IDF and burners come on and will cycle on the therm for temp. If fan left in auto the unit will not do anything. I disconected the therm wires at unit and jumped out r-w1 no action but r-w1 and g unit starts. The ignitor module and limin switch were replaced July,2012

I've never seen a module in a 2005 Carrier RTU. Can you post a pic?

AND...

Have you inspected that heat exchanger??????

[2sac]

I'm curious as to why the igc board and limit were replaced in July. Were they causing issues in a/c mode?

[COMFORTHVAC]

I'm curious as to why the igc board and limit were replaced in July. Were they causing issues in a/c mode?

THERE WAS A PROBLEM WITH THE A/C IN JULY AND AT THAT TIME THE INDUCER WAS RUNNING ALL THE TIME LIKE THE ROLL OUT WAS OPEN BUT IT WAS NOT BUT FOR THE PRICE OF THE ROLL OUT I REPLACED IT WITH THE CONTROL. IT HAS A W/R TWO STAGE HEAT AND COOL THERM.

[2sac]

Once the igc goes into lockout the inducer stays on even after the limit becomes closed. This would have been indicated by the flashing red light. Next question. You said you disconnected the t-stat and then jumped out. Was this done at the unit or inside by the thermostat?

[COMFORTHVAC]

Once the igc goes into lockout the inducer stays on even after the limit becomes closed. This would have been indicated by the flashing red light. Next question. You said you disconnected the t-stat and then jumped out. Was this done at the unit or inside by the thermostat?

I jumped at the unit. r-w1 no change have to jump r-g once the r-g jumper is touched you can remove the jumper and just leave the r -w1 and the unit will keep on running.

[Dallas Duster]

What is the complete 16 digit model number?

I jumped at the unit. r-w1 no change have to jump r-g once the r-g jumper is touched you can remove the jumper and just leave the r -w1 and the unit will keep on running.

[COMFORTHVAC]

48tme012-a-501

[2sac]

On the icb, when you installed it did you reverse the L1 blower tap with the L1 combustion tap?

[Dallas Duster]

But wouldn't he get a combustion fan failure?

On the icb, when you installed it did you reverse the L1 blower tap with the L1 combustion tap?

[2sac]

But wouldn't he get a combustion fan failure?

That makes sense unless he has the jumper on r, w and g @ the same time. He hasn't mentioned any error codes either.