Assertion: category iv furnace | /r/HasProperty | installed as non-direct vent appliances
Facets:
value: sometimes
type: TEMPORAL
Source sentences:
text: Although it is not recommended, Category III furnaces are sometimes installed as non-direct vent appliances where the combustion air is drawn from the CAZ and enters the furnace through a port on the combustion chamber, while exhaust gases vent to the outside via the single vent pipe.