Abstract: A furnace of the type for supplying circulating heated air to an comfort space, the furnace being contained within a cabinet, having a door allowing access to the interior thereof, which is set in a door frame, wherein the furnace is capable of operating in at least any vertical orientation, an improvement comprising. The bottom end of the door is removably retained against a bottom portion of the door frame, via a hinge, when the furnace is any vertical orientation. At least one latch is located adjacent the top end of the door when the furnace is in any vertical orientation, the latch being constructed to engage a mated door strike; and at least one door strike is located in both a top portion and a bottom portion of the door frame.

Abstract: A front access door suitable for accessing and enclosing a housing within a multipoise furnace functions in conjunction with a safety shutoff switch to provide greater access and safety when assembling and servicing the furnace. The front access door is hingably supported upon the bottom wall of the housing for removal from the furnace and rotation between a closed position and an opened position. The shutoff switch is mounted outside the housing on the top housing wall. When the access door moves into a closed position, a switch activator, mounted to the access door, passes over the top housing wall and closes the switch, thereby allowing power to flow to a blower within the housing. When the access door is moved into an open position, the switch activator opens the switch, thereby terminating power to the blower.