F228794 SPARK PLUG FLAME SENSOR KIT FOR MR HEATER

The F228794 Spark Plug Kit by Mr Heater is the LN03 series Spark Plug used on several Mr Heater and HeatStar heaters although this Old Style Spark Plug has been replaced with a Spark Plug Service Kit

This Old Style F228794 Spark Plug Kit was used by Mr Heater and Heatstar on the line of portable construction heaters including the following models:

Heatstar:
HS170FAVT Forced Air Construction Heater

Mr. Heater:
MH170FAVT Forced Air Construction Heater

Service Note:

The F228794 Spark Plug replacement kit instruction to covert to the new style sensor are as follows:


1.) Make sure the gas hose is not connected & the unit is unplugged from a power source before beginning the next steps.

2.)Take off bottom cover by removing the 4 support screws, carefully cut the zip tie at the wire bundle with the sleeve, the set of wires nearest the motor assembly/fan side of the unit (will not have the space to extract the motor until doing this step).

3.)Remove the 6 screws that mount the motor assembly into the unit. There are two at the top, two on the left & two on the right.

4.) Use a 13/16 socket or wrench with a long enough extension to reach inside the barrel of the heater from the motor end to loosen the nut on the spark plug. Once unloosened, the spark plug is to be removed from the unit along with the red ignitor wire that was connected to it. Remove this wire from the control board also, it will be replaced with the new wire in the retro-fit kit.

5.) Once the spark plug has been completely removed, place new ignitor into the same hole & use the self-tapping screw (#10 included in the kit) to mount it through the bracket hole & the heat shield as shown. (see picture in overview)

6.) Swap the red ignitor wire with the wire provided in the replacement kit. Plug the new wire into control board & route it through the same hole the original wire was routed through.

7.) Remount the motor/ bottom plate & replace the zip tie.