Replace flame sensor N8MSN0901714B3

2lefthands

Hello. Any help would be appreciates. Hoping I can do this repair! I have the following furnace:

N8MSN0901714B3

I believe my flame sensor needs to be replaced - looks like the wire is melting?

I think I found the right part, but it has a clip on the end of it and my white wire doesn’t - just seems to connect with a bunch of other wires at the power source.

https://www.technicalhotandcoldparts.com/icp-1190383-flame-sensor-w/-lead/

How do I proceed?

mattmia2

Show us where it connects to the control board in the blower compartment. also reroute it under the gas line so it isn't as close to the main burner. it looks like it just plugs on to the electrode.

109A_5

Typically the flame sensor is not too hard to replace, looks like only one screw in this case. Looks like the connector has been dilapidated by the heat, which seems odd, maybe there is something else may going on causing that issue, the 1/4" connector on the end of the wire may need to be replaced too. Or the whole wire all the way back to the control board. If that connection is poor the burner may fail to stay lit.

HVACNUT

Check all Grounds if that sensor cable is burned.

Steamheatnewboiler

How did you kmow it was bad?

2lefthands

I bought the new flame sensor. Issue is it has this plastic connector on the end. Do I cut off the plastic piece and cut the old flame sensor from the wire in my system? Then use a spade connectors to join the 2?

2lefthands

If I cut off the old sensor and cut the plastic piece of the new connector, can I use a WAGO to connect the new sensor to my system wire?

109A_5

Unless there is a connector hidden under the black split loom sheathing (Red arrow) the new sensor has a wire pigtail that is really is not needed.

You probably don't need the wire pigtail (Orange arrow), I would unplug it at the Green arrow. I would carefully remove the melted mess on the original wire and inspect the wires integrity into the connector. If OK I would put some heat shrink tubing (available at some auto-parts stores) over the connector like the black shrink tubing on the new sensors wire pigtail. As much as a WAGO connector may work I would not do it that way. You still may have an issue why it melted in the first place.

2lefthands

The old wire is quite difficult to work with since it’s just hanging there, that’s why I want to snip it. Not sure I can do what you’re suggesting.

If not a WAGO, is there any other options for connecting the 2 wires together?

EBEBRATT-Ed

You can buy spade connectors 1 male and 1 female cut the connector crip the new ones on and that will give you a disconnect point.

Home depot: Look this # up

Internet # 337829132

Model # 27ISA10363

You don't need the whole kit obviously you can buy them in many places in smaller quantities.

That said I don't think a WAGO is the worst solution, but I would prefer a crimp connection.

109A_5

Yes, you could cut off both these items pictures below and strip the insulation off the wires use the WAGO and it would probably work fine. A crimp butt splice or the male / female connectors as @EBEBRATT-Ed suggested would work too or you could just cut off the melted connector and replace it with a female one, since the actual sensor connector looks like a Male. Crimping requires crimp tool.

As long as there is a good connection from the sensor to the control board it should work fine. You also could cut off the connectors pictured below and solder the wires together and heat shrink the connection, many ways to get it done, however if it looks and performs like factory original that is best, no one can complain about the workmanship.