Vented Appliance Categories


Mechanical Code

Vented Appliance Category 1

An appliance that operates with a non-positive vent static pressure and with a vent gas temperature that avoids excessive condensate production in the vent.

Vented Appliance Category 2

An appliance that operates with a non-positive vent static pressure and with a vent gas temperature that may cause excessive condensate production in the vent.

Vented Appliance Category 3

An appliance that operates with a positive vent static pressure and with a vent gas temperature that avoids excessive condensate production in the vent.

Vented Appliance Category 4

An appliance that operates with a positive vent static pressure and with a vent gas temperature that may cause excessive condensate production in the vent.

(Uniform Mechanical Code® 224.0)