DeDietrich GT 220 A Operating Instructions Manual page 10

3. Boiler Venting & Chimney General
Caution & Warning:
It is advised and recommended that the heating contractor-professional apply vent materials that are approved and agency listed.
Installation of any venting must follow all local codes in conjunction with vent manufacturer instructions and appliance manufacturer
instructions.
All De Dietri ch GT se ries oil-gas fired cast iron b oilers are high performance boilers that co uld operate under all 4 ve nt
categories a s e stablished by ANSI Z2 1.13/CSA 4. 9 Standa rd. To a ssist wit h appli cation whe re th e vent cate gory is
unknown a g raph bel ow h as been p rovided to a ssist you in determining th e v ent catego ry and what ve nting mate rials
would be a cceptable. Alth ough the g as vent catego ries were developed sp ecifically for ga s fired appli ances, usin g this
information is helpful for oil fired boilers . It is very important the venting be sel ected according to the con ditions that the
boiler will operate under, minimum and maximum firing conditions of the boiler must be respected. The venting i nstalled
must comply and be certified to all applicable codes and standards for each jurisdiction.
Gas-Vent Category [4] Definitions:
Cat. I
A Boiler, w hich operates with a non-positive vent (breech) pressure
and flue gas temperatu res which avoids excessive
production in the chamber and venting.
Cat. II
A Boiler, w hich operates with a non-positive vent (breech) pressure
and flue gas temperatu res prod uce condensation production in the
chamber and venting.
Chart created by Craig Holdforth
6
500
456
412
368
324
280
236
192
148
104
60
82274096
Venting
condensation
Gas-Fired Appliance Vent Categorization
[According to ANSI Z21.13/CSA 4.9 Gas Boiler Standard]
7 8 9 10
Category I
Typical Vent Types [A,B,C & L]
Category II
Typical Vent Types
[BH, AL294C®, 304-316L SS]
Negative
Cat. III
A Boiler, w hich operates with a positive vent (breech) pressure and
flue gas temperatures
production in the chamber and venting.
Cat. IV
A Boiler, w hich operates with a positive vent (breech) pressure and
flue gas tempe ratures produces condensation production in
chamber and venting.
Chart A
Carbon Dioxide [CO ] Content %
2
11 12 11 10
Typical Vent Types
[BH, AL294C®, 304-316L SS]
[BH, AL294C®, 304-316L SS]
Chimney-Vent Pressure
[Inches w.c.]
which avoids exce ssive condensation
9 8 7
Category III
Category IV
Typical Vent Types
Positive
th e
6
260
236
211
187
162
138
113
89
64
40
15
27
11-20-09