This unit was BRAND NEW when we moved in and we only used it for one winter (maybe like 2 months). It's a great unit, nothing wrong with it but we got an entirely new HVAC system in our house so we had to take this unit out and have no use for it anymore. This unit retails for $800 plus! Here is the official description from the website:

Williams Furnace Company 500982 50,000 BTU Monterey Plus Top Vent Double Sided Wall Furnace
Product Code: WILLIAMS-FURNACE-500982


Williams Furnace Company 500982 50,000 BTU Monterey Plus Double Side Wall Furnace

Winter can be brutal - the process of choosing a furnace doesn't have to be. The Monterey top-vent wall furnace by Williams Furnace Company is a highly efficient indoor heating unit that, operating at 50,000 BTU, works to safely distribute heat throughout any indoor space at minimal cost.

Easily installed as a recessed or as a surface-mount unit, this double-side furnace is great for use in homes, schools, cabins, apartments, and shops, for ample heat and comfort wherever it is required. Because this unit is double-sided, it may be installed for the purpose of heating two adjacent rooms at once, for added heat and added convenience. Equipped with a "matchless" pilot ignition and automatic thermostat, this unit does not require electricity to run, allowing it to perform sufficiently even in the event of a power outage. This unit is a top-vent furnace, which means that it is vented vertically up through the roof, so that all combustibles discharge directly outside. This way, the unit is able to be centrally (and safely) located inside the home and installed on the indoor wall of your choosing.

With this furnace, you can even install two standard 100 CFM blowers (model 2901) - one on each side of your Monterey furnace. A blower improves circulation of warm air and reduces temperature differences in the room.

NOTE: Electricity is required to operate blower

Made in the USA

-May be installed surface-mount or recessed in the wall
-This unit is double-sided, which means it may be installed to heat two adjacent rooms simultaneously
- Unique wall-mount design requires no floor space
-No electricity required! Works even during power outages.
-All models include a "matchless" pilot igniter, for safe and easy pilot lighting
-Standard features include automatic temperature and safety controls, and a resettable vent-limit safety switch
-Included thermostat may be wall mounted or cabinet mounted
-Thermostat operates from 50- to 90-degrees Fahrenheit
- Patented, side-relief opening draft hood reduces flue gas temperature to minimize normal heat loss
-Natural Gas or Liquid Propane models available
-Featured in a soft-white, scratch resistant finish
$400.00 or best offer