______________________________________________________________________ Model# GUIO75AO12A1NW Serial# R920700039 This furnace is approx 12 yrs old and the fan will not shut off at times.I’ve had serveral service calls and had the delay time from when the furnace stops firing to the time the fan stops set to minmum but the fan still runs to the next heat cycle blowing cold air the whole time.Other then that no one knows what the problem is.This is an intermitent problem. Canuck [this message was edited by Canuck 32 on Sun 3 Oct 18:12] Replies: adamsmrbig “Re(1):Comfortmaker RPJ II” , posted Thu 8 Sep 18:05 ______________________________________________________________________ anyone have a wiring diagram for comfortmaker rpj2 they could email me please. i would really appreciate it. thanks for any help in advance draket “Re(2):Comfortmaker RPJ II” , posted Thu 26 Oct 09:33 ______________________________________________________________________ I have a wiriring diagram for a a comfortmaker RPJ2. Do you still need it? Tyrone Drake Xenos Webmaster “Re(1):Comfortmaker RPJ II” , posted Sun 3 Oct 18:14 ______________________________________________________________________ when the furnace is running what is the supply air temperature? Xenos. The best way to escape a problem is to solve it. Canuck 32 “Re(2):Comfortmaker RPJ II” , posted Sun 3 Oct 18:19 ______________________________________________________________________ I’m only guessing but it should be about 16-19C it’s not outside air. Canuck Xenos Webmaster “Re(3):Comfortmaker RPJ II” , posted Sun 3 Oct 18:38 ______________________________________________________________________ No the supply air, the air temperature leaving the furnace and entering the home. It may be too hot. Xenos. The best way to escape a problem is to solve it. Canuck 32 “Re(4):Comfortmaker RPJ II” , posted Sun 3 Oct 18:59 ______________________________________________________________________ I’m not sure when the furnace if firing but after it stops proucing heat it’s around 20-22C and the fan still runs Canuck Xenos Webmaster “Re(5):Comfortmaker RPJ II” , posted Sun 3 Oct 19:55 ______________________________________________________________________ Well the answer to your problem may be the supply air temperature. You have had techs out so what ever it is it’s not obvious and it’s likely an averheating problem. Xenos. The best way to escape a problem is to solve it. Mastertech “Re(6):Comfortmaker RPJ II” , posted Sun 3 Oct 20:06 ______________________________________________________________________ When the fan is running when its not suppose to turn the fan switch on at the T-stat does the fan speed change? Mastertech “Re(7):Comfortmaker RPJ II” , posted Sun 3 Oct 23:51 ______________________________________________________________________ Does this unit have a silver rectange box in the center of the furnace or a black box? Canuck 32 “Re(8):Comfortmaker RPJ II” , posted Mon 4 Oct 09:40 ______________________________________________________________________ The only box that I can see is a greyish clor and it’s mounted to the fan (The Gerneral,Intercity Products Model#50A50-131)I’ve tried restarting the furnace but the fan still comes on when I restart,the only why to shut the fan off is shutting power off to the furnace. Canuck Canuck 32 “Re(7):Comfortmaker RPJ II” , posted Sun 3 Oct 22:21 ______________________________________________________________________ No.I can even turn the switch on my t-stat from heat to the off position and the fan still runs with no speed change or from auto to on and same happens.I don’t understand how overheatin could be an issue,when the fan runs on there is no extra heat coming from the registers then ambient air temp and when it’s firing i can stand on the register right above the furnace and it’s not uncomfortable Canuck Mastertech “Re(8):Comfortmaker RPJ II” , posted Mon 4 Oct 11:04 ______________________________________________________________________ The 50A50 board is a single stage heater. Verify by looking at the terminals on the board and let me know what they are. Ex. (W1,W2,G,R,Y,C) Canuck 32 “Re(9):Comfortmaker RPJ II” , posted Mon 4 Oct 11:39: ______________________________________________________________________ Is that the rectangular box you were asking about?The only terminals i could see that match what you asked for are on the right hand side of the box,starting from bottom they read Y W R G C and the YandG are not being used Canuck [this message was edited by Canuck 32 on Mon 4 Oct 11:41] Xenos Webmaster “Re(8):Comfortmaker RPJ II” , posted Mon 4 Oct 08:00 ______________________________________________________________________ Well maybe the main board is the problem. What ever it is its not easily diagnosed I’ve had several service calls. What the thought of the overheating Is, on some units if the furnace overheats once during a cycle it will run the fan non stop. If it trips more than 3 times in one hour it will lock out the system. Xenos. The best way to escape a problem is to solve it. Canuck 32 “Re(9):Comfortmaker RPJ II” , posted Mon 4 Oct 09:09 ______________________________________________________________________ Any good guesses what aboard will run me? Canuck Mastertech “Re(10):Comfortmaker RPJ II” , posted Mon 4 Oct 11:46 ______________________________________________________________________ Yes that is the control board probably next to the blower. U have a single stage heater. I must say that G must be hooked up for fan to run. There should be 2 sets of wires coming to the board or to the furnace. One set may be 2 wire bundle and the other 5 or 8 wire bundlde do u see them both and where do the go. Ex 2wire bundle white goes to C and red goes to yellow wire with wire nut. mastertech “Re(2):Re(10):Comfortmaker RPJ II” , posted Mon 4 Oct 12:18 ______________________________________________________________________ Sry thats not he bundle im looking for. These bundles of wire come from outside the unit. Most likely brown wraped and then 18 to 20gauge wire. One set will come with the copper lines from out side and the other from the T-stat. These wire will be hook to the terminals Y,G,W,R,C. Hope that helps. Canuck 32 “Re(3):Re(10):Comfortmaker RPJ II” , posted Mon 4 Oct 15:18: ______________________________________________________________________ Man this is gettin confuzin.Ok on my t-stat i have a Wht,Blk,Red and green.I don’t have A/C so I’m not using the green and I don’t have my fan “on” option hooked up so the red is not used.I have a humidistat and there is one wire running to C which is marked as T-stat on the board, and another goin to the R,and my t-stat has the Blk goin to R and the Wht goin to W,the W is the gas valve and the R is the motor,correct?Confused yet? Canuck [this message was edited by Canuck 32 on Mon 4 Oct 15:20] Canuck 32 “Re(2):Re(10):Comfortmaker RPJ II” , posted Mon 4 Oct 12:11 ______________________________________________________________________ The colors were a little hard to see but here goes 4 bundle Blk-IND, Blk-IGN, Wht-INDN, Wht-INGN. 12 bundle Yellow-TH, Purple-TR,Orange-MV, Orange-MV,Wht-FPI, Orange-ROI,Grn-GND, Orange-RO2, Brown-HLO, Brown-HL1, Red-PS the FP2 is not used. Canuck Mastertech “Re(3):Re(10):Comfortmaker RPJ II” , posted Mon 4 Oct 15:55 ______________________________________________________________________ Okay this is the way to wire up On the control board to T-stat. R to R, W to W, G to G(if u want fan option). The new T-stat is not needed since u only have a 1 stage furnace. R is for power 24v. W is for heating G is for fan Y is for cooling(u dont use) C for comon(Some T-stats require C to work). To Check heat Jump W and R wires together. Heat should work. Mastertech “Re(4):Re(10):Comfortmaker RPJ II” , posted Mon 4 Oct 16:35 ______________________________________________________________________ It just strange to me but i guess yes. If u wire to what i gave u last time it should work if no problem. Good luck and let me know what happen. Canuck 32 “Re(4):Re(10):Comfortmaker RPJ II” , posted Mon 4 Oct 16:31 ______________________________________________________________________ Ok I’ll try it but do u think this has anything to do with my problem or is this just correcting someone’s bad wiring? Canuck Canuck 32 “Re(5):Re(10):Comfortmaker RPJ II” , posted Mon 4 Oct 18:35 ______________________________________________________________________ I have one of my humidistat wires running to the C terminal is that ok? Canuck Mastertech “Re(6):Re(10):Comfortmaker RPJ II” , posted Mon 4 Oct 18:57 ______________________________________________________________________ Try it with out, If it works then hook it up. hvacmgr “Re(7):Re(10):Comfortmaker RPJ II” , posted Mon 4 Oct 21:31 ______________________________________________________________________ The White Rodgers board should have a flash code on it. You are probably getting either a 2 or 3 flash. Check the flash code first. Are the venter motor AND blower motor running together and blowing cold air? If so you probably have an open limit or stuck pressure switch. Check those out. Does the ignitor glow? Mastertech “Re(8):Re(10):Comfortmaker RPJ II” , posted Mon 4 Oct 22:10 ______________________________________________________________________ How did it go. Does the heater come on? Or the fan work? Canuck 32 “Re(8):Re(10):Comfortmaker RPJ II” , posted Mon 4 Oct 22:01 ______________________________________________________________________ re hvacmgr: do you mean does the igniter glow during these periods that the fan is ruuning constant? Canuck hvacmgr “Re(9):Re(10):Comfortmaker RPJ II” , posted Wed 6 Oct 19:16 ______________________________________________________________________ Sorry, did not have internet access for two days ! No, I was curious if the ignitor tried to glow at any point in the cycle. If you reset power, does the ignitor try to glow? If not, then you either have a pressure switch stuck or an open limit. Check this if you can.