Raypak HD401 Installation & Operating Instructions Manual page 27

each appliance. Adjust thermostat so appliance
will operate continuously.
e) Check the pressure at a pressure tap located 12
in. above the bottom joint of the first vertical vent
pipe. Pressure should be anywhere between -.01
to -.08 in. WC.
f) After it has been determined that each appliance
remaining connected to the common venting sys-
tem properly vents when tested as outlined above,
return doors, windows, exhaust fans, fireplace
dampers and other gas burning appliances to their
previous conditions of use.
Model
No.
HD101
HD151
HD201
HD251
HD301
HD401
Maximum 4 elbows.
Fig. 21: Horizontal Thru-wall Venting (Category III)
Certified
Appliance
Venting
Category
Material
Stainless
III Steel
(Gas Tight)
Table L: Horizontal Thru-wall Venting (Category III)
g) Any improper operation of the common venting
system should be corrected so that the installation
conforms with the latest edition of the NFGC (US)
and the B149 Installation Code (Canada). When
re-sizing any portion of the common venting sys-
tem, the common venting system should be
re-sized to approach the minimum size as deter-
mined using the appropriate tables in Appendix G
in the NFGC (US) and Appendix B of the B149
Installation Code (Canada).
Vent Size
(inches)
4
5
6
27
Max. Venting
Length (feet)
100