problematic furnace

[gabriel84]

i'm a student in college studying hvac. i'm having a problem with the furnace i'm working on. its flashing a code but we don't have the manual or book to look up the codes. it a payne high effiency furnace. as soon as i put power to it the light starts to blink its pattern.
i'm looking for some information on this type of furnace or if anyone knows where you can find information like manuals somewhere online.

Manufacturer: Payne (Series B)
Product #: PG8DAA048115ABJA
Model #: PG8DAA048115
Serial #: 2998A16493

[kermy]

Could be broken loop in a safety device circuit. You probably don't need a manual... just a multimeter. Good luck!

[referrob]

not enough info. what is the blink sequence it is flashing? the back of the door panel should have a sticker (or the front of the blower housing cover), that explains trouble codes and possible causes. IE: 1 slow 2 fast then pause and repeat = blower on after power up with a call for heat. if your instructor cant help with this he/she has no business teaching hvac.

[gabriel84]

what was happening is we were connecting a wire between the "r" and "w" terminal to get an amperage rating to set the heat anticipator of the TStat. when we powered up the furnace, the blower turned on right away and the light started to flash a code. but we didn't have the gas valve open. so i'm thinking maybe there is a switch to sense the gas pressure coming in? not sure about that one.
we checked the flame roll out switches but i don't think they were the problem.

[coolwhip]

aux. lim.

[Ron]

code you are likely seeing is 1 short, 2 long = power on during call for heat. In other words, stat is calling but there is no power, then power is turned on and code flashes, blower runs 1 1/2 minutes, shuts off , heating cycle starts.