Vent Elbows; Barometric Damper; Automatic Vent Damper; Flue Connection - Patterson-Kelley MOD-04 Installation And Owner's Manual

®
Modu-Fire Gas-Fired Boiler
WARNING!
This boiler should not be installed with an automatic
damper on the flue. Damper failure could create an
explosion hazard.
In Canada, the boiler is certified for installation with a
"Power Venter" by the Canadian Gas Association
when installed with the "listed accessories." Consult
your local distributor for information on proper selec-
tion.
The venting system and the horizontal portions of the
venting system shall be supported to prevent sagging.
Consult your local vent supplier for correct vent sizing
and structural support requirements. Vent diameter is
dictated by the length and height of horizontal and ver-
tical portions of the vent installation and the materials
of construction. It is not necessarily the same size as
the boiler connection. Correct sizing should be based
on High fire input at a nominal -.04" w.c. draft pres-
sure at the boiler outlet with a gross stack temp of 325º
F and CO ratings at 7.5%.
2

3.6.1 Vent Elbows

Pitch toward
boiler 1/4" per
foot minimum.
6' min.
Condensate Line
To sewer trap or
condensate drain.
The first turn from horizontal to vertical should be
made with a 135° boot tee. A tee cover with a conden-
sate drain shall be provided at the bottom of the boot
Boot Tee /135º
Tee
Trap Loop
3" min.
8
tee. The condensate drain must be routed to a sewer
drain trap or pump in accordance with local codes.
Refer to diagram under Vent Elbows.

3.6.2 Barometric Damper

This boiler is certified for operation without a baro-
metric damper. P-K does not recommend the use of
one.

3.6.3 Automatic Vent Damper

WARNING!
This equipment, as manufactured, MUST NOT be
used with an automatic vent damper.

3.6.4 Flue Connection

The connection from the boiler to the vent should be
as direct as possible and the upward slope of any hori-
zontal breaching should be at least 1/4 inch per linear
foot. This boiler should not be connected into any por-
tion of a mechanical draft system operating under
positive pressure. Provisions must be made for sup-
ports to prevent contact of the vent with combustible
surfaces.
Note: Make sure that the weight of the vent is not
supported by the boiler vent collar. The collar is not
designed to support the weight of the vent. Structural
support and spacing from combustible surfaces must
be in accordance with the vent manufacturer's re-
quirements.

3.6.5 Vent Termination

The minimum vent height above the flue outlet must
be five (5) feet and the vent should extend at least
three (3) feet above the roof / snowline, or at least two
(2) feet above the highest part of any structure within
ten (10) feet of the vent.
Installation