Bryant 398AAV Ignitor glows, no flame


  #1  
Old 11-27-15, 05:49 PM
J
Member
Thread Starter
Join Date: Aug 2009
Location: Los Angeles, CA
Posts: 6
Received 0 Votes on 0 Posts
Bryant 398AAV Ignitor glows, no flame

I have a 23 year old Bryant 398AAV Plus 90 furnace. The ignitor glows, but no flame. I don't measure any voltage at the gas valve, at either wire to ground or across the gas valve terminals.

It cycles through 3 ignitor on/off cycles. Pressure switch works (open/closed). Hot limit switch is 0 ohms (closed). There is a small transformer mounted on the control board -- I don't measure any voltages at input terminals PR-1 or PR-2, or output terminals SEC-1 or SEC-2.

Thanks for any help you can provide
 
  #2  
Old 11-27-15, 07:13 PM
Houston204's Avatar
Forum Topic Moderator
Join Date: Oct 2009
Location: Texas
Posts: 7,536
Received 38 Votes on 34 Posts
It sounds like you may have a problem with your multimeter.
If you don't have voltage from the transformer the ignitor shouldn't glow.

Are you measuring for voltage AC or DC?
How long has it been since your meter has shown you 24 volts AC?
Can you measure 120 volts AC on anything else in the house to prove that it isn't time for a new meter?

Does the call for heating stop when you turn off the thermostat?
Can the thermostat control the fan?
 
  #3  
Old 11-27-15, 09:14 PM
J
Member
Thread Starter
Join Date: Aug 2009
Location: Los Angeles, CA
Posts: 6
Received 0 Votes on 0 Posts
Houston204: Very good guess on your part.

No problem with the multimeter -- cockpit problem I had the meter set for auto, thinking it would show AC voltage. Nope. Fixed that, now the small transformer shows 120 volt at the input, 30 volts at the output.

Thermostat can call for heat, fan on setting turns on the fan.

Rechecked voltage across gas valve (Blue & Brown wires) with meter on AC setting. Still no voltage during or after ignitor glows.
 
  #4  
Old 11-27-15, 09:52 PM
Houston204's Avatar
Forum Topic Moderator
Join Date: Oct 2009
Location: Texas
Posts: 7,536
Received 38 Votes on 34 Posts
Can you post a picture of the wiring diagram?

Are there any safety switches between the control board and the gas valve?
 
  #5  
Old 11-27-15, 11:41 PM
J
Member
Thread Starter
Join Date: Aug 2009
Location: Los Angeles, CA
Posts: 6
Received 0 Votes on 0 Posts
No safety switches between control board and gas valve.

I turned the gas off, removed the brown wire at the gas valve, and ran a jumper wire from the R terminal (+24 volts) on the control board to the terminal on the gas valve where the brown wire was. You could hear the gas valve actuate. I am pretty sure the gas valve is working OK.

I check the resistance of the flame rollout switch, the pressure switch, and the large square brown over temp switch. All were 0 ohms (closed).

I scanned my wiring diagram, too large to attach. Took a picture & compressed, not readable. It is Bryant part number CES0110057-00
 
  #6  
Old 11-28-15, 12:19 AM
Houston204's Avatar
Forum Topic Moderator
Join Date: Oct 2009
Location: Texas
Posts: 7,536
Received 38 Votes on 34 Posts
While it wouldn't make much sense for the ignitor to glow without a satisfied pressure switch,I think that I have seen some older models do this.

This old Carrier has a spill switch and a pressure switch in the circuit that feeds the gas valve...


Measure for 24 volts across the pressure switch after the induced draft motor runs for a few seconds.

Save the image as a JPEG and post the IMG on this site using www.photobucket.com
 
  #7  
Old 11-28-15, 02:24 AM
J
Member
Thread Starter
Join Date: Aug 2009
Location: Los Angeles, CA
Posts: 6
Received 0 Votes on 0 Posts
Heater by jointodayjames | Photobucket

this link shows the wiring diagram to my heater. (I hope I did this right)
 
  #8  
Old 11-28-15, 12:13 PM
Houston204's Avatar
Forum Topic Moderator
Join Date: Oct 2009
Location: Texas
Posts: 7,536
Received 38 Votes on 34 Posts


There is nothing else on the circuit to the gas valve but I would check the pressure switch.

If you left click the IMG on photobucket you can right click and paste here.

Most manuals have a number on the first or last page. It may be possible to bring up that manual in digital format.
 
  #9  
Old 11-28-15, 01:40 PM
SeattlePioneer's Avatar
Banned. Rule And/Or Policy Violation
Join Date: Jul 2007
Location: Seattle, Wa
Posts: 5,499
Received 1 Vote on 1 Post
The ignitor should heat up for thirty seconds or so.

Then the circuit board should turn on the 24 VAC voltage to the gas valve, the main burner gas valve should open, gas should come out the burner orifices and light off the hot surface ignitor.

Since that last step isn't happening, here are things to check out:


1 You need to be SURE that you have gas pressure to the electric gas valve! Be sure that the gas meter is turned on, that the manual shutoff valve at the furnace is turned on and that the electric gas valve is turned to the on position.

Personally, I'd shut off the manual gas valve and open the pipe union or flex connector at the furnace and crack open the manual gas valve to be SURE that you have gas pressure.

2. Check to see if the 24 VAC to the electric gas valve is being turned on after the HSI heats up. If it is, you have a bad gas valve.

3. If you aren't getting that 24 VAC switched on to the electric gas valve, you have a bad circuit board.
 
  #10  
Old 11-28-15, 02:42 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 70,055
Received 2,952 Votes on 2,664 Posts
Since the OP checked the valve with power.... that is out of the equation.
A common problem is the multipin connector where the plugs connects to the board. The pins can loosen or become corroded.
 
  #11  
Old 11-29-15, 06:18 PM
J
Member
Thread Starter
Join Date: Aug 2009
Location: Los Angeles, CA
Posts: 6
Received 0 Votes on 0 Posts
Thanks for everyone's help troubleshooting this.

The gas stove, oven, and water heater work OK, so I am sure gas is coming into the house.

I am not measuring 24 volts into the gas valve. I tried unplugging & plugging in the connector a couple times, thinking it might clean the contacts if that was the problem, but it still doesn't work. I also tried tapping on one of the relays on the board. Still doesn't work

I ended up ordering a replacement board (ICM281). Hopefully this is a good brand & it fixes the problem.

Even in Los Angeles, it gets in the mid 40's at night now. Thank god for electric blankets. I don't know how folks survive where it really gets cold!
 
 

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