Purge Of Supply Duct; Hardware - Weather-Rite XT112 Installation, Operation & Service Manual

S XT I , O
ERIES NSTALLATION PERATION AND

3.2 Purge of Supply Duct

If this heating unit is to be installed indoors, and its
outdoor air supply ducted from outdoors, ANSI
Standards Z83.4/CSA 3.7, Z83.18 and Z83.25/CSA
3.19 require that all supply duct shall be purged a
minimum of four times prior to any ignition attempt. If
the volume of the outdoor air supply duct exceeds
the heating unit's ability to complete the required four
air changes prior to ignition, you must contact the
factory to purchase an extended purge card of the
appropriate duration to meet this requirement.

3.3 Hardware

Unless otherwise specified, all hardware must be
torqued to settings on Page 6, Table 1.
Note: Inlet hood opening shall not be installed with
inlet opening facing into the prevailing wind direction
in order to help prevent the possibility of moisture
entrainment.
6
S M
ERVICE ANUAL
Table 1: Recommended Torque Settings
Bolt Head
Grade Marking
Nut Grade
Marking
Bolt Size Grade 2
10-24 27 in•lb
1/4-20 65 in•lb
5/16-18 11 ft•lb
3/8-16 19 ft•lb
8.8
Bolt Head
Grade Marking
8.8
Nut Grade
Marking
Bolt Size Grade 8.8
M5 6Nm
M6 10Nm
M8 25Nm
M10 50Nm
M12 85Nm
M16 215Nm
Grade 5
42 in•lb
101 in•lb
17 ft•lb
30 ft•lb
10.9
10.9
Grade 10.9
9Nm
15Nm
35Nm
75Nm
130Nm
315Nm