Modine Manufacturing HD Installation And Service Manual - page 5
5
5. Test all draft hood equipped appliances for spillage at the
draft hood relief openings after 5 minutes of main burner
operation. Use the flame of a match or candle.
6. After it has been determined that each appliance connected
to the venting system properly vents when tested as outlined
above, return doors, windows, exhaust fans, fireplace
dampers and any other gas-burning appliance to their
previous conditions of use.
7. If improper venting is observed during any of the above
tests, the venting system must be corrected.
8. If the venting system must be resized, it must conform with
the National Fuel Gas Code ANSI Z223.1 or CAN/CGA
B149.1 or .2 Installation Code-latest edition. If the venting
system must be resized, it should be resized to approach the
minimum size as determined using the appropriate table in
Appendix G of the National Fuel Gas Code ANSI Z223.1.
Note: A vent is the vertical passageway used to convey flue gases from
the unit or the vent connector to the outside atmosphere. A vent
connector is the pipe which connects the unit to a vent or chimney.
Vent connectors serving Category I appliances shall not be connected
into any portion of mechanical draft systems operating under positive
pressure.
Venting Instructions
1. All vertically vented HD heaters are category I venting. All
horizontally vented HD heaters are category III venting.
2. Using Table 1, determine the venting requirements for the
category determined above. A category III heater must
conform to the venting requirements called out in Table 1,
which are detailed in the following sections, as well as
additional requirements also detailed in following sections.
3. Vertically vented heaters may be vented with either single
wall or double wall vent pipe. Follow the double wall
manufacturers clearances to combustibles.
4. All HD heaters come with a factory installed vent adapter for
attaching the vent pipe to the heater. Attach the vent pipe to
the adapter with 3 non-corrosive screws. (Drill pilot holes
through the vent pipe and adapter prior to screwing in place)
5. Do not use any vent pipe smaller than 3". Refer to the
National Fuel Gas Code for the minimum material thickness.
6. A minimum of 12" straight pipe is recommended from the
power exhauster outlet before turns in the vent system.
Suspend horizontal runs at a minimum of 3' intervals.
7. Avoid venting through unheated spaces when possible.
When single wall pipe does pass through an unheated
space, insulate runs greater than 5' to minimize
condensation. Inspect for leakage prior to insulating and use
insulation that is noncombustible with a rating of not less
350°F. Install a tee fitting at the low point of the vent system
and provide a drip leg with a cleanout cap as shown in
Figures 4 and 5. The drip leg should be cleaned annually.
8. Keep single wall vent pipe at least 6" from combustible
material. The minimum distance from combustible material is
based on the combustible material surface not exceeding
160°F. Clearances from the vent pipe (or top of the unit) may
be required to be greater than the minimum clearance if heat
damage (such as material distortion or discoloration) may
occur.
9. When a single wall vent passes through a combustible wall
or floor, a listed thimble must be used. When a type B
double wall vent passes through a combustible wall or floor,
follow the vent pipe manufacturers clearances to
combustibles. Refer to Figure 3.
10. This heater is equipped with a power exhaust system. DO
NOT use any additional power exhaust systems or vent
dampers. FAILURE TO FOLLOW THESE INSTRUCTIONS
could result in serious injury or death.
11. All vertically vented HD heaters are category I and must be
connected to a factory built chimney or vent complying with
a recognized standard, or a masonry (or concrete) lined
chimney with a material acceptable to the authority having
jurisdiction. Venting into an unlined masonry chimney is not
permitted. Refer to the National Fuel Gas Code for common
venting.
12. Secure all vent joints with at least 3 corrosion-resistant
screws. Use an approved vent terminal to reduce down
drafts and moisture in the vent.
13. The vent must terminate no less than 5' above the vent
connector. The top of the vertical stack should extend above
any portion of a building within a horizontal distance of 2'
(see Figure 4).
14. For pitched roof vertical venting, refer to the National Fuel
Gas Code for the vertical distance that the cap must extend
above the pitched roof.
INSTALLATION
Table 1
ANSI Unit Heater Venting Requirements
Venting
Category
Description
Requirements
I
Negative vent pressure
Follow standard
Non-condensing
venting requirements.
II
Negative vent pressure
Condensate must
Condensing
be drained.
III
Positive vent pressure
Vent must be gas tight.
Non-condensing
IV
Positive vent pressure
Vent must be liquid and
Condensing
gastight. Condensate
must be drained.
Figure 3
Venting Through Combustible Floor or Roof
*
See Instructions for attaching single wall pipe to double wall pipe (page 6)
Listed
Cap
Flashing
Listed
Thimble
Listed
Cap
Flashing
Clearance Specified
by Type B Vent Mfg.
Modine
Specified Cap
(See No.4,
page 6)
Clearance Specified
by Type B Vent Mfg.
Listed
Thimble
Single Wall Vent Pipe
*
Double Wall Vent Pipe
Venting Through Combustible Wall
Modine
Specified Cap
(See No.4,
page 6)
*
Double Wall Vent Pipe
Single Wall Vent Pipe