Our basement unit York Diamond 80 runs and run with the ignitor working and the blower running but does not heat up the first floor. The unit in the attic heats the first floor fine. The exhaust vent seems to be extremely hot. Is it possible the motor that exhausts the cabon monoxide from the gas fumes is running tto fast? The heat coming out of the registers is only reading 76.5. It has been running for three hours straight. The temp in the house is 61 degrees - upstairs is 65. Outside is 22. HELP

You are only getting a 15 degree TD across the heat exchanger and that is low on output. Check to make sure the furnace filter is clean. If the unit is burning there is not much else you can do but call for an ON Site Inspection of your unit to determine the problem.

What was the temperature before you turned the furnace on?

It was 60 degrees. It got down to -2.5 degress here in the Washington suburbs last night but the furnace clearly could not keek upo. It probably ran for 6 hrs staright. Tonight it ran for three hours before shutting off for 5 minutes only to run again for 30 minutes. It warmedup to 23 degrees and is suppose to warm up. It seems like it can not keep up eben though the Diamond 80 unit in the attic which is much colder has no problems keeping up - it is smaller biut only heats the seond floor. The unit for the basement and 1st floor just seems to run all the time.

Suggestions?

You need to call for On Site srevice to get it looked into. I can do nothing from here with yor description. It is a good possibility that the unit needs to have the gas pressure checked to see if it meets the imput rate for the burner.