5532522-UIM-B-0619
Johnson Controls Ducted Systems
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3. The duct shall be least the same cross-sectional area as the free
area of the air supply inlet opening to which it connects.
4. The blocking effects of louvers, grilles and screens must be given
consideration in calculating free area. If the free area of a specific
louver or grille is not known. Refer to Table 5 to estimate free area.
Ventilated Combustion Air
The ventilated attic space or a crawl space from which the combustion
air is taken must comply with the requirements specified in “AIR
SOURCE FROM OUTDOORS” in this instruction or in Section 5.3, Air
for Combustion and Ventilation of the National Fuel Gas Code, ANSI
Z223.1 (latest edition). This type installation requires two properly sized
pipes. One brings combustion air from a properly ventilated attic space
or crawl space and a second pipe that extends from the furnace vent
connection (top right of unit) to the exterior of the building.
Vent and Supply (Outside) Air Safety Check Procedure
For Category I furnaces, vent installations shall be in accordance with
Parts 7 and 11 of the National Fuel Gas Code, ANSI Z223.1/NFPA 54,
and or Section 7 and Appendix B of the CSA B149.1, Natural Gas and
Propane Installation Codes, the local building codes, furnace and vent
manufacturer's instructions.
Multi-story or common venting systems are permitted and must be
installed in accordance with the National Fuel Gas Code, ANSI Z223.1/
NFPA 54 and / or the CSA B149.1, Natural Gas and Propane Installa-
tion Codes, local codes, and the manufacturer's instructions.
Vent connectors serving Category I furnaces shall not be connected
into any portion of mechanical draft systems operating under positive
pressure.
Horizontal portions of the venting system shall be supported to prevent
sagging using hangers or perforated straps and must slope upwards
not less than 1/4” per foot (21 mm/m) from the furnace to the vent termi-
nal.
It is recommended that you follow the venting safety procedure below.
This procedure is designed to detect an inadequate ventilation system
that can cause the appliances in the area to operate improperly causing
unsafe levels of Carbon Monoxide or an unsafe condition to occur.
SECTION VII: START-UP AND
ADJUSTMENTS
The following start-up checks
MUST
be performed by the furnace
installer on every new furnace installation.
1. Gas piping leak check
2. Ignition check
3. Furnace input rate check
4. Air temperature rise check
Instructions on how to perform each of these required installation
checks are listed in the sections below.
When the gas supply is initially connected to the furnace, the gas piping
may be full of air. In order to purge this air, it is recommended that the
ground union be loosened until the odor of gas is detected. When gas is
detected, immediately retighten the union and check for leaks. Allow
five minutes for any gas to dissipate before continuing with the start-up
procedure. Be sure proper ventilation is available to dilute and carry
away any vented gas.
WARNING
CARBON MONOXIDE POISONING HAZARD
Failure to follow the steps outlined below for each appliance connected to the venting system being placed into operation could result in carbon-
monxide poisoning or death.
The following steps shall be followed for each appliance connected to the venting system being placed into operation, while all other appliances
connected to the venting system are not in operation:
1. Inspect the venting system for proper size and horizontal pitch. Determine that there is no blockage, restriction, leakage, corrosion or other defi-
ciencies, which could cause an unsafe condition
2. Close all building doors and windows.
3. Turn on clothes dryers and TURN ON any exhaust fans, such as range hoods and bathroom exhausts, so they shall operate at maximum
speed. Open the fireplace dampers. Do not operate a summer exhaust fan.
4. Follow the lighting instructions. Place the appliance being inspected in operation. Adjust thermostat so the appliance shall operate continu-
ously.
5. Test each appliance (such as a water heater) equipped with a draft hood for spillage (down-draft or no draft) at the draft hood relief opening
after 5 minutes of main burner operation. Appliances that do not have draft hoods need to be checked at the vent pipe as close to the appliance
as possible. Use a combustion analyzer to check the CO
2
and CO levels of each appliance. Use a draft gauge to check for a downdraft or inad-
equate draft condition.
6. After it has been determined that each appliance properly vents when tested as outlined above, return doors, windows, exhaust fans, fireplace
dampers and any other gas burning appliance to their normal condition.
7. If improper venting is observed during any of the above tests, a problem exists with either the venting system or the appliance does not have
enough combustion air (Supply Air from outside) to complete combustion. This condition must be corrected before the appliance can function
safely.
NOTE:
An unsafe condition exists when the CO reading exceeds 40 ppm and the draft reading is not in excess of - 0.1” w.c. (-25 kPa) with all
of the appliance(s) operating at the same time.
8. Any corrections to the venting system and / or to the supply (outside) air system must be in accordance with the National Fuel Gas Code
Z223.1 or CAN/CGA B149.1 Natural Gas and Propane Installation Code (latest editions). If the vent system must be resized, follow the appro-
priate tables in Appendix G of the above codes or for this appliance.
!
IMPORTANT:
All electrical connections made in the field and in the
factory should be checked for proper tightness.
