Choctaw H140 flame detector

[cancunlarry]

Does anyone know the nsn number for the flame detector wiring harnes?

Larry

 

[155mm]

flame detectors have the wiring built in, its sold as an assembly, wires and sensor

 

[155mm]

@Guyfang also might move this to 'other-auxiliary-equipment' forum not govplanet gen questions

 

[155mm]

Does anyone know the nsn number for the flame detector wiring harnes?

Larry

@cancunlarry is there more to this question? like the wires for the flame detector got burned off the sensor

 

[cancunlarry]

@cancunlarry is there more to this question? like the wires for the flame detector got burned off the sensor

When I tried to pull the sensor out of the tube assembly on the burner, the flame detector detached from the wiring. The flame detector was stuck in the tube assembly. I have replaced these before and all the other times the flame detector has detached easily, but this time the assembly broke and I had to pull the sensor out with plyers.
Larry

 

[cancunlarry]

@Guyfang also might move this to 'other-auxiliary-equipment' forum not govplanet gen questions

will do thanks for the advice

 

[155mm]

best off the shelf replacements I can find are

Honeywell C554a
Westwood E80,

E81 is cad cell eye only for both manufactures

if you order, make sure you get the correct length leads, some were short as 6" or as long as 60"

 

[cancunlarry]

best off the shelf replacements I can find are

Honeywell C554a
Westwood E80,

E81 is cad cell eye only for both manufactures

if you order, make sure you get the correct length leads, some were short as 6" or as long as 60"

Do you know how to test the flame detector. I have another heater that I use for parts and I could use that one, but I would like to check it before. I was reading that you can shine a flashlight and use my multimeter. I just don't know what readings I am supposed to get. It has two wires and the sheathing goes to a ground. The two wires from the detector goes to the combustion control K1. Can I test the flame detector while its hooked up?

 

[155mm]

@cancunlarry

short short version, if there is a flame, 2000 ohms or less, prefer less than 1000 ohms from wires F to F at K8 relay on H82, or

wire TB3-1 and wire TB3-2 from terminal board TB3

I think those are the right leads on the h140

 

[cancunlarry]

@cancunlarry

short short version, if there is a flame, 2000 ohms or less, prefer less than 1000 ohms from wires F to F at K8 relay on H82, or

wire TB3-1 and wire TB3-2 from terminal board TB3

I think those are the right leads on the h140




View attachment 915664

 

[cancunlarry]

@cancunlarry

short short version, if there is a flame, 2000 ohms or less, prefer less than 1000 ohms from wires F to F at K8 relay on H82, or

wire TB3-1 and wire TB3-2 from terminal board TB3

I think those are the right leads on the h140




View attachment 915664

OK this helps. The flame detector has 2 wires and yes they both go to TB3-1 and TB3-2. I turn the S1 switch on the machine to vent and I purge the line for 10 seconds. Then I turn the machine to cool and I can see the flame through the looking glass, and the combustion fan is running. Then I turn the S1 to heat mode. Wait 5 seconds and The heater never fires up and occasionally the flame out light will come on. Normally within 15 seconds.
I assume the flame out comes from the controller not detecting a flame. In the TM it sends me through a list of things to check if there is no combustion.
I check the all the wires going to and from the temp sensors on the burner. All of them work.

If I am reading the article above correctly to bypass the sensor:
1.) I start the machine in vent mode and purge the line.
2.)I set the machine to cool down. confirm I have a flame. and put a jumper wire on TB3-1 terminal screw.
3.)I turn the machine to heat mode, and immediately connect my other jumper wire to TB3-2. In theory this should tell the controller that there is a flame and by pass the flame out. If I do this, I can deduct 2 things
a.)If the unit fires up and I get heat. It must be the flame detector.
b.)If the unit does not fire up, I must have a fuel problem or solenoid issue. Right?

If I want to test the sensor :
1.)I start the machine in vent mode and purge the line.
2.)I set the machine to cool down and check for a flame. If a flame is present I should put my probes on TB3-1 and TB3-2 and get an ohm reading. If the reading is 1,000 or less my sensor is good. If my reading is above 1,000 ohms the sensor is bad or not positioned correctly....Right?
3.)OR does the heater need to be in combustion mode producing heat to test the sensor?

Much appreciated!
Larry

 

[155mm]

OK this helps. The flame detector has 2 wires and yes they both go to TB3-1 and TB3-2. I turn the S1 switch on the machine to vent and I purge the line for 10 seconds. Then I turn the machine to cool and I can see the flame (spark not flame) through the looking glass, and the combustion fan is running. Then I turn the S1 to heat mode. Wait 5 seconds and The heater never fires up (so no flame for flame detector to detect, its a fuel or injector problem) and occasionally the flame out light will come on. Normally within 15 seconds.
I assume the flame out comes from the controller not detecting a flame. In the TM it sends me through a list of things to check if there is no combustion.
I check the all the wires going to and from the temp sensors on the burner. All of them work.

If I am reading the article above correctly to bypass the sensor:
1.) I start the machine in vent mode and purge the line.
2.)I set the machine to cool down. confirm I have a flame. (spark no flame in cool down mode) and put a jumper wire on TB3-1 terminal screw.
3.)I turn the machine to heat mode, and immediately connect my other jumper wire to TB3-2. In theory this should tell the controller that there is a flame and by pass the flame out. If I do this, I can deduct 2 things
a.)If the unit fires up and I get heat. It must be the flame detector.
b.)If the unit does not fire up, I must have a fuel problem or solenoid issue. Right?

If I want to test the sensor :
1.)I start the machine in vent mode and purge the line.
2.)I set the machine to cool down and check for a flame.(no flame in cool down, only spark) If a flame is present (in heat mode with flame present) I should put my probes on TB3-1 and TB3-2 and get an ohm reading. If the reading is 1,000 or less my sensor is good. If my reading is above 1,000 ohms the sensor is bad or not positioned correctly....Right?
3.)OR does the heater need to be in combustion mode producing heat to test the sensor? (must be in heat mode with good flame for sensor to detect)

Much appreciated!
Larry