Part No.
550-100-268/1220
Hazard defi nitions
Th e following defi ned terms are used throughout these Instructions to bring attention to the presence of hazards of
various risk levels or to important information concerning the life of the product.
Indicates presence of hazards that can cause severe personal injury, death or substantial property damage.
Indicates special instructions on installation, operation or maintenance that are important but not related
to personal injury or property damage.
Vent Category II Addendum Boiler Manual
KEEP THIS ADDENDUM WITH BOILER MANUAL
This Addendum adds to and supercedes items in the “Evergreen Boiler Manual”
(Part Number 550-100-131) and previously released Addenda’s.
Evergreen Boilers
(EVG 220, EVG 299/300, and EVG 399)
can now be vented in a Category II
confi guration.
In addition to the
Evergreen
boiler’s Category IV rating (positive pressure, likely to condense),
Evergreen
boilers are approved for Category II (negative pressure, likely to condense) as well.
This new venting option includes / requires:
• The Vent system for a Category II
Evergreen
boiler is considered a Designed / Engineered vent system
and should be designed by a professional using accepted engineering practices in accordance to local
authority having jurisdiction.
• Vertical Vent only.
• Must not be installed into an existing common vent system with other appliances.
• Combustion air must come from the boiler room. See Boiler Room Air opening requirements in this
Addendum.
• Must increase venting to 6” using a 6” to 4” bell reducer at boiler vent adapter for Category II Vent
Connection.
• The Vent System should be designed so that the pressure in the 6” vent pipe immediately following
the bell reducer is between the ranges provided in the Table 1, page 2, during all running (burner lit)
conditions (i.e., High Fire through Low Fire).
• Flue gas temperature should not exceed 210°F; the boiler will shut down and recycle if it does. The
fl ue gas temperature should typically be within 20°F of the return water temperature of the boiler.
If there is the potential for a wide variation in return water temperatures, the lowest possible tem-
perature should be used for any calculations.
- continued on next page
CONDENSING GAS BOILER
220/299/300/399
