Old Carrier Problems


  #1  
Old 01-26-10, 01:51 PM
J
Member
Thread Starter
Join Date: Jan 2010
Location: United States
Posts: 4
Upvotes: 0
Received 0 Upvotes on 0 Posts
Old Carrier Problems

Hello, I have a Carrier 58EJA Gas-Fired Horizontal Condensing Furnace. In late October I replaced the HSI and the furnace worked fine. Just before Christmas it stopped working again i.e. it would start the fan would start then shut-off after 15 seconds or so. The only way to get it started was to turn the power off and on. So, thinking it may be a condensate problem, I replaced the pump (it need to be replaced anyway). The same problem existed. So, I cleaned of the flame sensor and re-crimped the flame sensor wire along with taping any worn areas of the wire. I started it up and it worked fine until a couple of days ago where it would not ignite again. What is my next step? I don't want to purchase a new unit. Is it the flame sensor? Thanks in advance for you responses.
 
  #2  
Old 01-26-10, 04:57 PM
Houston204's Avatar
Forum Topic Moderator
Join Date: Oct 2009
Location: Texas
Posts: 6,532
Received 95 Upvotes on 88 Posts
http://www.docs.hvacpartners.com/idc.../58eja-2sm.pdf


Clean the flame sensor with some steel wool.
Clean the condensate drain as described in page 3 (Step 4).

Remove and clean ground connection from the ignition control to the furnace body.
Verify that field installed ground wire is connected to the furnace.

 
  #3  
Old 01-26-10, 05:43 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
There are two fans ---- a small one called the inducer motor which circulates the combustion gasses and the much larger one that circulates air around the dwelling space. Which one is turning on?

And does the hot surface ignitor glow white hot to light the gas?

What made you suspicious of a condensate drain problem? Do you hear water sloshing around when the inducer fan is running?
 
  #4  
Old 01-26-10, 09:14 PM
J
Member
Thread Starter
Join Date: Jan 2010
Location: United States
Posts: 4
Upvotes: 0
Received 0 Upvotes on 0 Posts
@Houston:I already cleaned the sensor with 320-grit paper. Initial inspection did show tiny amounts of oxidation, but it was easily removed. I will clean out the drain system as you suggest. Thank you.

@SeattlePioneer: The induction motor runs initially, the HSI glows then the unit shuts down. When I cleaned the sensor and recrimped the sensor wire, I also had to splice and crimp because of bad wire insulation, the unit worked fine. It recently has stopped in the same manner as before I performed the sensor work. Regarding the condensate, I read somewhere that a bad pressure switch can cause the unit to shut down. I bypassed the pressure switch by connecting the leads to each other and the same problem occurred. So, I deduced that either the sensor is bad, there is a ground issue, or maybe the board. I am hoping it is just a bad sensor. Basically, I am performing the easiest less expensive options first and going from there. Thanks.

I would appreciate any additional input. Thanks again.
 
  #5  
Old 01-26-10, 09:49 PM
Houston204's Avatar
Forum Topic Moderator
Join Date: Oct 2009
Location: Texas
Posts: 6,532
Received 95 Upvotes on 88 Posts
Flame Rectification

"Many mechanics will replace the ignition module, then think they've solved the problem because the ignition system begins to operate normally. In reality, what has often happened is that by reconnecting the wires to the module, they've changed the ground connection and improved the sensing signal. In many cases, they may have achieved the same results by simply disconnecting and reconnecting the wires on the ignition module they thought was faulty."



Verify a good ground to your board. I've been behind another tech that had replaced a control board only to find a faulty ground connection.
 
  #6  
Old 01-27-10, 01:19 AM
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
The inducer motor should turn on, the HSI should heat up and then the main burner gas should switch on and light off the HSI.

It's really not clear at what point this sequence of ignition stops. You need to be very clear on that point.
 
  #7  
Old 01-27-10, 01:58 PM
J
Member
Thread Starter
Join Date: Jan 2010
Location: United States
Posts: 4
Upvotes: 0
Received 0 Upvotes on 0 Posts
Well gentlemen it is running. I turned the power on and off and it ran just like it supposed to. Anyway, I did remove the cover of the control board apparatus and tightened the ground along with checking the ground at the switch and it looked OK. While looking at the wiring diagram I did notice that P1 was completely bypassed and P2 was the only pressure switch connected. If P2 is the unit closest to the induction motor. I did reroute the wire to the flame sensor further away from the burners because I noticed charring on the wire. Other than that, it seems to be working fine. Why would the P1 switch be bypassed? Thanks.
 
  #8  
Old 01-28-10, 09:11 AM
J
Member
Thread Starter
Join Date: Jan 2010
Location: United States
Posts: 4
Upvotes: 0
Received 0 Upvotes on 0 Posts
Back Again

Now my induction motor is continuously running. Maybe I should move to a warmer climate. Wind chill at -8 today. Anyway, in my last post I mentioned that the P1 pressure switch was not connected it appears that only P2 is being utilized? Why would someone bypass the switch? Is this causing the motor to run all the time? The temp in the house is now dropping. I am about ready to throw a hand grenade into the crawl space.
 

Last edited by joeycap; 01-28-10 at 09:59 AM.
  #9  
Old 01-28-10, 12:31 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
From the circuit diagram, it looks like there are two pressure switches in series with each other and in series with some other safety switches such as a flame rollout switch.

It's unusual to have two pressure switches ---- presumably they are testing the proper operation of different parts of the furnace.

Since someone did a hack job on your furnace by disconnecting a pressure switch, you don't really know what else may be hacked up as well. I'd call a good repairman to inspect and repair the furnace and to make sure it's safe to operate when put back into service.
 
 

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