What is a Category 4 vent?
“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. These appliances are typically 87 to 97% efficient and are vented with plastic, stainless steel, or a material other than Class B or masonry.
How are Category IV furnaces generally vented?
How are Category IV furnaces generally vented? PVC venting. The difference between vent sizing for natural draft appliances and fan assisted appliances is that? PVC vent.
What is Category 3 vent?
Category III is defined as a gas heating appliance with a flue loss equal or greater than 17% (non-condensing) with a positive vent static pressure. In a Category III venting system, if there is a leak in the venting system, flue gas will flow from the flue pipe into the space.
What are the four functions of a venting system?
There are four purposes of ventilation: Provide a continuous supply of fresh outside air. Maintain temperature and humidity at comfortable levels. Reduce potential fire or explosion hazards.
What is the difference between a Category I furnace and a Category IV Furnace?
A Category I furnace operates with. A high temperature, negative pressure vent. A Category IV operates with? A low temperature, positive pressure vent.
What is CAT II venting?
Gas appliances are divided into four venting categories based on vent operating pressure and whether they are condensing or non-condensing. Category II is negative pressure, condensing. Category III is positive pressure, non-condensing. Category IV is positive pressure, condensing.
What is a Category 4 Furnace?
Category IV Appliances are mainly high efficiency water heaters and furnaces that use plastic vent pipes. These appliances also operate with positive vent pressure and cannot share a common vent with a gravity-vented water heater. Inspectors should not confuse fan-assisted furnaces with those that are power vented.
What is Z vent?
Z-Vent® double fail safe self-sealing Special Gas Vent System dramatically reduces installed vent system cost. Vent stack/breeching designed for use with boilers, high efficiency furnaces. Venting for both spa heaters and pool heaters, unit heaters, and water heaters.
Is B vent a Category 1?
The AmeriVent all-metal, double-wall gas vent is listed as Type B by Underwriters Laboratories, Inc. and is approved for such residential and commercial applications as Category 1 water heaters, boilers, furnaces, space heaters, or wall heaters.
What’s the difference between Category I and Category III venting?
In other words, in a Category I venting system, if there is a leak in the venting system, air from the space will flow into the flue pipe and no flue gas will flow into the space. Category III is defined as a gas heating appliance with a flue loss equal or greater than 17% (non-condensing) with a positive vent static pressure.
Can a water heater be used with a Category IV vent?
These appliances operate with positive vent pressure and, therefore, cannot be adjoined to a gravity-vented water heater. Category IV Appliances are mainly high efficiency water heaters and furnaces that use plastic vent pipes.
Can a common vent be used on a Category I furnace?
The text box at left, taken from an induced draft furnace instructions, clearly specifies common venting with Category I vents only. Many new furnaces now arrive with stickers stating that common venting is allowed because there has been so much confusion regarding these connections.
What makes a heating appliance a Category II or IV?
Category II and IV are for condensing gas heating appliance with a flue loss of less than 17%. In these appliances, the flue gas condenses from a gas to a corrosive liquid. These appliances have their own special venting requirements that we will deal with in a separate paper.