Goodman gas furnace: end switch open


  #1  
Old 01-16-16, 10:53 AM
B
Member
Thread Starter
Join Date: Jan 2016
Posts: 10
Upvotes: 0
Received 0 Upvotes on 0 Posts
Goodman gas furnace: end switch open

Hey,

I have a has furnance Goodman model PGB024075-1. I'm having problems getting the heat to come on (not sure about the ac) Currently the board is blinking red twice indicating that the end switch is open. It tells me to check the venter end switch. I've Google for that and haven't been able to find anything helpful. I've checked a couple of the obvious things. There are 240 volts coming into the plunger. The plunger wont go down, but I can push it down and the fan will turn on. If the system isn't calling for heat the red light is steady in the normal operation mode. I'm not sure what to do at this point. Any help would be much appreciated.

https://imageshack.us/i/p5gdIzuhj
https://imageshack.us/i/hl7pHIZDj

What I'm calling the plunger:
https://imageshack.us/i/p3xTr7Qej

I hope y'all can see those images

Thanks in advance!
 
  #2  
Old 01-16-16, 11:24 AM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 62,054
Received 3,420 Upvotes on 3,066 Posts
Welcome to the forums.

That "plunger" is called a contactor and controls the A/C compressor.
Since you have a furnace.. that contactor won't be active in the winter.

A two flash code is open pressure switch.
You need to check and see if the draft inducer blower is starting on a call for heat. The inducer is that little fan on the front of the furnace near the burner.
 
  #3  
Old 01-16-16, 12:32 PM
B
Member
Thread Starter
Join Date: Jan 2016
Posts: 10
Upvotes: 0
Received 0 Upvotes on 0 Posts
Thanks you. If that's something that I would hear, no, the fan is not spinning
 
  #4  
Old 01-16-16, 01:53 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 62,054
Received 3,420 Upvotes on 3,066 Posts
You have a packaged unit.... everything is outside. In the diagram.... the red circle should be where the flashing red LED is. The blue circled item is the inducer that needs to be running. The orange arrow is where the hot exhaust would normally come out. You'd here the draft inducer running very loudly at the exhaust port.

Name:  good.JPG
Views: 3459
Size:  48.4 KB
 
  #5  
Old 01-16-16, 02:43 PM
B
Member
Thread Starter
Join Date: Jan 2016
Posts: 10
Upvotes: 0
Received 0 Upvotes on 0 Posts
The machine is silent. The fan isn't running
 
  #6  
Old 01-16-16, 02:54 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 62,054
Received 3,420 Upvotes on 3,066 Posts
You're getting the two light flash code which means the board has power. You'd need to open the service door and check the inducer motor for 240vac to see if the board is not providing it or the motor is defective.

This is the inducer blower. The end switch is attached to it.

Name:  inducer.jpg
Views: 3413
Size:  35.8 KB
 
  #7  
Old 01-16-16, 03:24 PM
B
Member
Thread Starter
Join Date: Jan 2016
Posts: 10
Upvotes: 0
Received 0 Upvotes on 0 Posts
Thanks. I'll check that tomorrow and report back
 
  #8  
Old 01-17-16, 10:00 AM
B
Member
Thread Starter
Join Date: Jan 2016
Posts: 10
Upvotes: 0
Received 0 Upvotes on 0 Posts
I'm not positive I'm doing it correctly, but I checked the lead going into the inducer and there is no power. It's plugged into the D1 slot.

Also there is no buzz coming from the motor, so I feel confident power isn't getting to the inducer

https://imageshack.us/i/paBsQgjnj
Name:  fbb8db4c88fa02eee2ddf2f6ab8acba4.jpg
Views: 4014
Size:  36.4 KB
 

Last edited by PJmax; 01-17-16 at 11:00 AM. Reason: Add pic from link
  #9  
Old 01-17-16, 10:38 AM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 62,054
Received 3,420 Upvotes on 3,066 Posts
There are two wires that go to the inducer. One is on the D1 slot and the other is on an L2 slot.
You need to check between those two. Make sure the control board is blinking a code 2 while doing this. If not.... power down and then back up.

If the control board is not in "call for heat" mode there won't be 240vac there.

With power off to the entire unit..... you can set your meter to ohms scale and see if there is continuity between DI and L2.

Name:  test.JPG
Views: 3310
Size:  37.5 KB
 
  #10  
Old 01-17-16, 10:52 AM
B
Member
Thread Starter
Join Date: Jan 2016
Posts: 10
Upvotes: 0
Received 0 Upvotes on 0 Posts
The meter reads 240 and there is continuity between the two
 
  #11  
Old 01-17-16, 10:56 AM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 62,054
Received 3,420 Upvotes on 3,066 Posts
You checked the continuity with no power turned on ?

Take the leads off of D1 and L2. Check for continuity again. If you still have it..... the motor is frozen/stuck.
 
  #12  
Old 01-17-16, 11:36 AM
B
Member
Thread Starter
Join Date: Jan 2016
Posts: 10
Upvotes: 0
Received 0 Upvotes on 0 Posts
Sorry, I had it on the wrong setting. There is no continuity when the power is off
 
  #13  
Old 01-17-16, 11:52 AM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 62,054
Received 3,420 Upvotes on 3,066 Posts
Ok... so you have confirmed the 240v which means the control board is working.

Continuity shows open which means the motor windings have opened. That would be what I'd be expecting.

That means the inducer assembly needs to be replaced. This is just one place you could get it from.
Vent/Inducer Motor — B2959000S, Goodman/Janitrol | Goodman Repair Parts
 
  #14  
Old 01-17-16, 12:01 PM
B
Member
Thread Starter
Join Date: Jan 2016
Posts: 10
Upvotes: 0
Received 0 Upvotes on 0 Posts
Thanks a lot. Is there a way too test the motor before I replace it?
 
  #15  
Old 01-17-16, 12:15 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 62,054
Received 3,420 Upvotes on 3,066 Posts
You just did.

It needs 240v to run and you confirmed that.
The motor winding needs to be a complete and closed coil of wire. You used your ohmmeter to confirm that the winding is not closed but is open.

You can remove the four screws that hold it in place and see if the motor is frozen but at this time it's a moot point as the motor is defective.
 
  #16  
Old 01-17-16, 12:22 PM
B
Member
Thread Starter
Join Date: Jan 2016
Posts: 10
Upvotes: 0
Received 0 Upvotes on 0 Posts
Ok thanks a lot for all your help.

I'm just getting tricked up by what exactly you learned by there being no continuity. But I'm assuming that's because I don't understand the board and what it is trying to do.
 
  #17  
Old 01-17-16, 12:26 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 62,054
Received 3,420 Upvotes on 3,066 Posts
Any electric motor.... even your basic pedestal fan has a coil of very fine wire called the winding. That winding is connected to two wires which are then supplied power. So if that winding or coil is not a complete and closed loop..... nothing will happen. It's just like pulling a bulb out of a string of Christmas lights..... any open in the loop and everything is dead.

The board just supplies the power to run that blower at the proper time. That motor only runs during the course of heating. It doesn't run for the A/C.
 
  #18  
Old 01-27-16, 03:32 PM
B
Member
Thread Starter
Join Date: Jan 2016
Posts: 10
Upvotes: 0
Received 0 Upvotes on 0 Posts
Got the part in and everything is working smoothly again. Thank you very much for all your help!
 
  #19  
Old 01-27-16, 03:40 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 62,054
Received 3,420 Upvotes on 3,066 Posts
Tough repair..... good job.

Thanks for letting us know how you made out.
 
  #20  
Old 10-23-16, 11:59 AM
P
Member
Join Date: Oct 2016
Location: USA
Posts: 2
Upvotes: 0
Received 0 Upvotes on 0 Posts
Question for PJMax......

I have the exact same unit/problem as this gentleman except for my motor is buzzing when the heater tries to turn on. The A/C portion of this unit works perfectly.

Do I need a new vent motor as well?

I am an AV automation specialist and install smart thermostats for Google as well.
 
  #21  
Old 10-23-16, 12:06 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 62,054
Received 3,420 Upvotes on 3,066 Posts
Welcome to the forums.

Buzzing.... like motor frozen or stuck buzzing ?
If the motor isn't turning then it's frozen. It could be bad bearings or rust in the blower housing.
 
  #22  
Old 10-23-16, 12:35 PM
P
Member
Join Date: Oct 2016
Location: USA
Posts: 2
Upvotes: 0
Received 0 Upvotes on 0 Posts
I just cut power to the unit, went outside, spun the motor both ways a few times to clear any debris that may have accumulated over the past 7-8 months. It started right up. Thanks for all your help PJMax on this website.
 
  #23  
Old 10-23-16, 01:18 PM
SeattlePioneer's Avatar
Banned. Rule And/Or Policy Violation
Join Date: Jul 2007
Location: Seattle, Wa
Posts: 4,469
Upvotes: 0
Received 1 Upvote on 1 Post
Ummmm. `Very likely the motor is failing and will fail permanently before long.

What I would have done is to remove the motor assembly, usually held in place by three bolts or so and easy to remove. I'd inspect the fan for broken or detriorated blades or for a fan plugged with debris.

Also look through the hole into the furnace to see if there is any debris or water accumulating in the bottom of the heat exchanger which is exposed to view.

The turn the inducer motor fan to see if it turns freely or is obviously stiff and hard to turn, usually because the motor is failing.

Inducer motors typically can't be lubricated, so when they go bad you need to buy the inducer motor assembly, which consists of the motor, fan and sheet metal that allows the who assembly to be installed easily.

When this problem recurs, you can do these additional checks.

I'd also shop around NOW for a replacement inducer motor assembly. When it finally fails, you'll probably want to replace it in a hurry, and if you've already shopped for the part it will be easier for you.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: