Have HVAC Questions? Ask an HVAC Expert for Answers
I have a GMH950703BXAF Goodman I bought a Honeywell RTH8500WF Thermostat installed and someone messed up namely (ME)one of the wires. thought they would just take apart with no reference. The fuse on the main board was BLOW. replace that and have a heartbeat! But I have the red 3 code flashing.. lights Pressure switch stuck closed. it turns it on all you hear is the blower is just spinning. no control at t-stat. is there a manual reset for the presser switch? Need help with wiring?? I have 2 little wires that go the the ac unit outside. I think they connect to Y and C on the main board?
click to see pic https://docs.google.com/file/d/0B8Jr...hNM2N2MHM/edit Ac Out side unit https://docs.google.com/file/d/0B8Jr...dCeFYtNTA/edit to the main board inside wiring https://docs.google.com/file/d/0B8Jr...l1SGhsQlk/edit and here is the thermostat wiring https://docs.google.com/file/d/0B8Jr...R3b0d4LUE/edit You can see there us a 3wire red green white (red)Y (green) G (white) W and 2 wires (Red) R (White) C Now there is a pump on the side of the unit https://docs.google.com/file/d/0B8Jr...ZTeDFISGc/edit A pump of water needs 24 volts looks like it turns on when water needs to be pumped?
Hi, I'm Brian and my goal is to diligently answer your HVAC/R questions to your complete satisfaction! It sounds like you could use a helping hand. I'm here to help and hopefully we can figure your issue out together!
I see you are standing by, are you receiving my chat messages?
I am going to switch to the question/answer format instead of the chat format in case you are not receiving my chats.
First I want to thank you for the model numbers and the pictures. It really helps us when troubleshooting problems. Ok let's get to it. First let's tackle the wiring:The two wire cables from the thermostat and condensate pump:R/RC (red wire) on stat to red wire on condensate pump cable (use a small wire nut)White wire on condensate pump cable to R on ahu controlC (white wire) on stat to C on ahu controlThe Three wire cable from the thermostat:W (white wire) on stat to W on ahu controlY (red wire) on stat to Y on ahu controlG (green wire) on stat to G on ahu controlThe two wire cables going to the condenser (outside unit)White wire from condenser to C on ahu controlRed wire from condenser to Y on ahu controlThat will complete the thermostat wiring. The wire going to the condensate pump is a safety cut-off so if the condensate pump stops pumping water out it will stop the system and the unit won't produce anymore condensate so you won't have water everywhere.Now for the 3 flash code. You are correct that it relates to an inducer draft blower pressure switch issue but it is not stuck closed, it is indicating that the inducer blower is running but the pressure switch is not closing it's contacts to tell the system that it is ok to fire up the burner. There are quite a few things that could cause this. If the inducer is operating correctly and is supplying the burner with air properly then the problem lies with the pressure switch. The first thing I would do is (with the power off) disconnect the tubing and with a can of compressed air blow the tubing and fittings clear as sometimes they can get clogged. Reattach them and see if that worked. If that doesn't work make sure the flue or inducer air pipes are not clogged anywhere especially at the ends. Make sure the flue isn't filled with condensate from the furnace. Make sure the inducer blower wheel is attached securely to the inducer motor shaft and the blower wheel is clean. Those are the main things to check with an inducer airflow switch issue. If you still can't get the unit to work properly, please message back and I will troubleshoot the system further with you.Thanks for using Just Answer and good luck!
OK wiring Done.. thanks I remember you are correct with the wire nut..
the system is only a year old and work perfectly before I messed with it..
don't see any clogged tubes/ lines there is pvc piping running from the furnace to the out side as a vent
here a pic of the upper unit with the cover off
can you point out in picture
Well problem solved
Watch a u tube video on how a presser switch works in the a furnace . I am a automatic by trade, so i know how to test vacuum and operated switch.
Look like this system is in place so houses don't burn down!! You HVAC guy got us covered thanks.
Well problem solved right side presser switch stuck.. open
With vacuum left side OK right no continuity . With a little Blow and suck LOL it started I got continuity from the right side. System is up and running I think I should order a presser switch it may get stuck again..