Vacuum Switch Cumberland MF3700/ MF3800 - 28664 replaces 720238 & 720073

Vacuum Switch for Cumberland MF3700/ MF3800 multifuel/ pellet stoves. Part # 28664 replaces 720073 & 720238. Ardisam recently changed their OEM vacuum switch from the old style white with a clear plastic top to the standard gray and black switch as shown at right. The new switch will not mount the same way as the original. The vacuum switch is a safety switch that shuts the pellet stove down if the combustion (Exhaust) blower fails. If your pellet stove starts up then stops feeding pellets after the start cycle is over, then the vacuum switch is bad or the vacuum line is clogged with ash. Also, if the auger motor does not turn you may have a bad vacuum switch.

• This part can be easily accessed by removing the right side

panel. It is located on the back of the firebox.

• It is retained with screws. Use a ¼" socket to remove them.

Remove the vacuum hose that attaches to the brass nipple

screwed into the firebox. Unplug wires to remove switch