Desa Comfort Glow CGR35NA Quick start guide

Save this manual for future reference.
WARNING: If the information in this manual
is not followed exactly, a fire or explosion
may result causing property damage, per-
sonal injury, or loss of life.
FOR YOUR SAFETY
— Do not store or use gasoline or other
flammable vapors and liquids in the
vicinity of this or any other appliance.
— WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electrical switch; do
not use any phone in your building.
• Immediatelycallyourgassupplierfrom
a neighbor’s phone. Follow the gas
supplier’s instructions.
• If you cannot reach your gas supplier,
call the fire department.
— Installation and service must be per-
formed by a qualified installer, service
agency, or the gas supplier.
WARNING: Improper installation,
adjustment, alteration, service, or
maintenance can cause property
damage, personal injury or loss of
life. Refer to this manual for cor-
rect installation and operational
procedures. For assistance or
additional information consult a
qualified installer, service agency,
or the gas supplier.
®
VENTED NATURAL
GAS HEATERS
Models: CGR65BNA, CGR65NA, CGR50BNA, CGR50NA, CGR35NA
OWNER’S OPERATION AND INSTALLATION MANUAL
®

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100792
CONTENTS SECTION PAGE
Safety Information.........................................................................3
Product Identification .................................................................... 5
Local Codes ...................................................................................6
Unpacking ....................................................................................6
Product Features ............................................................................6
Installing Heater ............................................................................ 6
Check Gas Type...................................................................... 6
Installation Items..................................................................... 6
Locating Heater....................................................................... 7
Venting Heater ........................................................................ 8
Connecting to Gas Supply ...................................................... 11
Checking Gas Connections..................................................... 13
Installing Radiants ..................................................................14
Installing Glass Panel ............................................................. 15
Air For Combustion and Ventilation............................................. 17
Determining Fresh-Air Flow for Heater Location
Example 1: Locating Heater in Unconfined (Open) Area 18
Draft Hood Spillage Test............................................ 18
Providing Permanent Fresh-Air Ventilation ..............19
Example 2: Locating Heater in Confined (Closed) Area..20
Ventilating Confined Area ......................................... 20
Operating Heater ........................................................................... 21
For Your Safety Read Before Lighting .................................. 21
Lighting Instructions............................................................... 21
Manual Lighting Procedure ....................................................23
Blower Operation (For Models with Blower) ........................23
To Turn Off Gas To Appliance ..............................................23
Inspecting Pilot and Burner Flame................................................ 24
Pilot Flame Pattern..................................................................24
Burner Flame Pattern ..............................................................24
Cleaning and Maintenance ............................................................ 26
Troubleshooting............................................................................. 27
Service Procedures ........................................................................ 32
Removing Control Valve and Burner Tube............................32
Removing Burner.................................................................... 33
Changing Burner Orifice ........................................................ 34
Blower Wiring Diagram................................................................ 34
Technical Service .......................................................................... 35
Specifications ................................................................................ 35
Service Hints ................................................................................. 35
Ordering Replacement Parts.......................................................... 36
Parts Centrals................................................................................. 36
Accessories ....................................................................................37
Illustrated Parts List ...................................................................... 38-41
Warranty Information.................................................................... Back Cover

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100792
SAFETY
INFORMATION
Continued
WARNING ICON G 001
WARNINGS
IMPORTANT: Read this owner’s manual carefully and completely be-
foretrying toassemble, operate, orservice thisheater. Improperuse of
thisheatercancauseseriousinjuryordeathfromburns,fire,explosion,
electrical shock, and carbon monoxide poisoning.
WARNING ICON G 001
DANGER
Carbon monoxide poisoning may lead to death!
Carbon Monoxide Poisoning: Early signs of carbon monoxide poisoning
resemble the flu, with headaches, dizziness, or nausea. If you have these signs, the
heater may not be operating or venting properly. Getfresh airat once!Have heater
or heater venting system serviced. Some people are more affected by carbon
monoxide than others. These include pregnant women, people with heart or lung
disease or anemia, those under the influence of alcohol, and those at high altitudes.
NaturalGas:Naturalgasisodorless.Anodor-makingagentisaddedtonaturalgas.
The odor helps you detect a natural gas leak. However, the odor added to natural gas
can fade. Natural gas may be present even though no odor exists.
Makecertain you read and understandallWarnings.Keepthis manual for reference.
It is your guide to safe and proper operation of this heater.
1. A qualified service person must install heater and venting system.
2. Use only natural gas. Do not convert heater to use different fuel type.
3. If you smell gas
• Shut off gas supply.
• Do not try to light any appliance.
• Do not touch any electrical switch; do not use any phone in your building.
• Immediately call your gas supplier from a neighbor’s phone. Follow the gas
supplier’s instructions.
• If you cannot reach your gas supplier, call the fire department.
4. Thisheatermusthave fresh air for proper operation. If not, poor fuel combustion
andimproperventingoffluegases will result. Carbon monoxide poisoning from
backed-up flue gases could occur. The State of California lists carbon monoxide
as a reproductive toxin under Proposition 65. Read the instructions under Air for
Combustion and Ventilation, pages 17 through 20 for complete information.
5. Never install the heater
• in a mobile home or a recreational vehicle.
• where curtains, furniture, clothing, or other flammable objects are less than 48
inches from the front, 53 inches from top, or 12 inches from right side and 6
inches from left side and back of heater.
• directly on carpeting, tile, or other combustible materials other than wood
flooring. Place heater on metal or wood panel extending the full width and
depth of heater.
• as a fireplace insert.
• in high traffic areas.
• in windy or drafty areas.

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100792
SAFETY
INFORMATION
Continued
WARNING ICON G001
WARNINGS Continued
6. Providethe following minimum heater clearances from combustibles (as viewed
from the front of heater):
Front: 48 inches
Back: 6 inches
Top: 53 inches
Right Side: 12 inches
Left Side: 6 inches
7. Do not run heater
• where flammable liquids or vapors are used or stored
• under dusty conditions
8. Never place clothing or any flammable objects on the heater or venting system.
9. Heater and venting system surfaces are very hot during operation. Keep children
and adults away from hot surfaces to avoid burns or clothing ignition. Carefully
supervise young children when they are in the same room as heater. Heater will
remain hot for a time after shutdown. Let surface cool before touching.
10. Do not use heater as a cooking device.
11. Do not alter heater or its controls. Any change may create a safety hazard.
12. Turn off heater and unplug (if equipped with blower) and let cool before
servicing. Unless you need gas supply for testing, shut off manual shutoff valve
beforeservicing. Onlyaqualified service personshouldservice and repairheater
and venting system.
13. Replace any safety screen or guard removed for servicing before running heater.
14. Do not use heater if any part has been under water. Immediately call a qualified
servicepersontoinspecttheheaterandtoreplaceanypartofthecontrolsystemand
any gas control which has been under water.

5
100792
Lower Front
Access Panel
Control
Knob
Blower Switch
(on models
equipped with
blower)
Ignitor
Button
Burner
Radiants
Draft Hood
Outlet for
Venting
System
Blower
(on models
equipped with
blower)
Figure 2 - Vented Natural Gas Heater, Rear View
Figure 1 - Vented Natural Gas Heater
Control
Valve
PRODUCT
IDENTIFICATION

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100792
Install and use heater with care. Follow all local codes. In the absence of local
codes, use the latest edition of the following:
• National Fuel Gas Code ANSI Z223.1, also known as NFPA 54 *
• National Electrical Code ANSI/NFPA 70 *
*Available from: American National Standards Institute, Inc.
1430 Broadway
New York, NY 10018
National Fire Protection Association, Inc.
Batterymarch Park
Quincy, MA 02269
PRODUCT
FEATURES
Piezo Ignition System
This heater has a piezo ignitor. This system requires no matches, batteries, or other
sources to light heater.
Thermostatic Heat Control
This heater has a thermostat sensing bulb and a control valve. This results in the
greatest heating comfort. This can also result in lower gas bills.
INSTALLING
HEATER
WARNING ICON G001
WARNING
A qualified service person must install heater and
venting system. Have them inspect heater before use
and at least annually. Follow all local codes.
NOTICE
Thisheatermustbeelectricallygroundedifequippedwith
blower. Follow all local codes. In the absence of local
codes, follow the National Electric Code, ANSI/NFPA 70.
UNPACKING 1. Remove heater from carton.
2. Remove all protective packaging applied to heater for shipment.
3. Check heater for any shipping damage. If heater is damaged, promptly inform
dealer where you bought heater.
LOCAL CODES
CHECK GAS TYPE
Use only natural gas. If your gas supply is not natural gas, do not install heater.
Call dealer where you bought heater for proper type heater.
INSTALLATION ITEMS
Before installing heater, make sure you have all items below.
• piping (check local codes)
• sealant (resistant to propane gas)
• manual shutoff valve *
• ground joint union
• test gauge connection * (see
Figure 7, page 12)
• sediment trap
• tee joint
• pipe wrench
• venting materials
* An A.G.A. design-certified manual shutoff valve with 1/8" NPT tap is an
acceptable alternative to test gauge connection. Purchase the optional A.G.A.
design-certified manual shutoff valve from your dealer. See Accessories, page 37.

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100792
INSTALLING
HEATER
Continued
LOCATING HEATER
WARNING ICON G001
WARNING
Maintain the minimum clearances shown in Figure 3,
below. If you can, provide greater clearances.
WARNING ICON G001
WARNING
Never install the heater
•in a mobile home or a recreational vehicle.
•where curtains, furniture, clothing, or other flam-
mable objects are less than 48 inches from the front,
53 inches from the top, 12 inches from the right side
and 6 inches from the left side and back of heater.
•directly on carpeting, tile, or other combustible
materials other than wood flooring. Place heater on
metal or wood panel extending the full width and
depth of heater.
•as a fireplace insert.
•in high traffic areas.
•in windy or drafty areas.
WARNING ICON G001
CAUTION
If you install the heater in a home garage
•heater pilot and burner must be at least 18 inches
above floor
•locate heater where moving vehicle will not hit it.
For convenience and efficiency, install heater
• where there is easy access for operation, inspection, and service.
• in coldest part of room.
• near an electrical outlet if heater has blower or if you are planning to add
blower to heater. See Accessories, page 37 for blower.
Figure 3 - Heater Clearances
53"
Minimum
CEILING
Left
Side
6"
Minimum
Right
Side
48" Minimum from
Front of Heater
6" Minimum
from Back
12"
Minimum
Continued

8
100792
Note: Venting/chimney materials are not supplied with heater.
VENTING HEATER
INSTALLING
HEATER
Continued
WARNING
When venting this heater, follow the safety information
listed below.
•Never vent heater to another room or inside a build-
ing. Only vent heater to the outdoors.
•Do not vent heater exhaust to a chimney or flue
serving another solid-fuel-burning or gas appliance.
•We recommend you use flues classified as prefabri-
cated or masonry all-fuel chimney or type-B vent. See
Vent Types, page 10.
•If using old vent, check vent for soot, creosote, and
loose particles. If vent is damaged, repair or replace
it before using heater.
•Extend the vertical section of vent pipe at least three
feet above roof penetration.
•Extend the vertical section of vent pipe at least two
feet above the highest point of any roof within ten
feet.
•The horizontal run of vent pipe should rise at least
1/4 inch for each foot of run.
•Support the vent pipe at least every five feet along its
length. Do not use combustible materials to support
vent pipe.
•Never extend vent pipe horizontally through outside
wall and terminate. You must connect a vertical run
of vent pipe to the horizontal run. The vertical run
must be at least 25% longer than the horizontal run.
•Install vent or chimney cap that is approved for use
with vented gas room heaters.
•Do not use vent pipe smaller in diameter than that of
the heater draft hood outlet.
•Do not use dampers in the vent pipes.
•Vertical height of vent must be greater than five feet
above vent connection at draft hood.
WARNING
This heater has a vent safety shut-off system. This
system shuts off the heater gas supply if you do not
vent heater properly or the venting system is blocked.
Do not operate heater if not properly vented. Do not
tamper with the vent safety shut-off system. Carbon
monoxide poisoning and death may result.
WARNING
A qualified service person must install the venting system
for this heater. If venting system is not properly installed
and maintained, the vent safety shut-off system will pre-
vent the heater from running. Follow all local codes.

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100792
INSTALLING
HEATER
Continued
Heater must be vented to the out-
doors. Never vent heater to another
room or inside a building.
The vertical section of vent pipe must
extend at least two feet above the
highest point of any roof within ten
feet.
Never extend vent pipe horizontally
through outside wall and terminate.
You must connect a vertical run of
vent pipe to the horizontal run. The
vertical run must be at least 25%
longer than the horizontal run.
Never extend vent pipe horizontally
through a chimney or flue. You must
connect a vertical run of vent pipe to
the horizontal run. The vertical run
must be at least 25% longer or five
feet minimum than the horizontal run.
Vertical run of pipe must be at least
five feet from elbow to elbow.
Figure 4 - Improper Venting Systems
Continued
VENTING HEATER (continued)
WARNING ICON G 001
WARNING
Do not vent heater in any of the following ways (see Figure 4).
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;;
Less than 5' between elbows

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100792
VENTING HEATER (continued)
INSTALLING
HEATER
Continued
Proper Size Vent
To safely vent heater, the vent connector pipe must be the same diameter as the draft
hood outlet on the rear of the heater. Pipe that is too small can cause flue gas to spill
fromtheheater.Fastenventconnectortothedrafthoodoutletwithasheetmetalscrew.
Vent Types
Prefabricated or Masonry All-Fuel Chimney - This is a masonry chimney or a
residential-type prefabricated chimney. Only use prefabricated chimneys listed by
Underwriters Laboratories (UL), Inc.
Type-B Vent - These vents are made of noncombustible, corrosion resistant
material. They are certified by a nationally recognized testing agency. Type-B
vents are double-walled pipe. Clearances to combustible construction must be in
accordance with the listing of the particular type-B vent. Type-B vents are cur-
rently listed as B-1, B-1 1/2, and B-2.
The illustrations below show both vent types. The illustration shows typical
construction of each type of venting system. Minimum clearances and lengths are
added to the illustrations.
Figure 5 - Typical Construction of Venting Systems
5'
Min.
Heater
Vent
Connector
Lock Joints
Vertical Vent
53"
Min.
Maintain Listed
Clearance of
Vent
Lock Joints
Position
Firestop Support
Laterals
Lock
Joints
Support If
Necessary
Maintain Listed
Clearance of Vent
Vent Cap
Must Be At
Least 2 Feet
Above
Highest Point
Within 10
Feet.
Seal Around
Collar and
Flashing
Type-B VentPrefabricated or Ma-
sonry All-Fuel Chimney
Heater
Terminate at least 5' above draft hood. If vent extends
over 5' above roof, support with guy wires or braces.
6"
Min.
Continued

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100792
INSTALLING
HEATER
Continued
CONNECTING TO GAS SUPPLY
The gas supply line to your heater must be 1/2 inch in diameter or larger. If the
supply line branches to serve two or more heaters, the line from the branch back to
the gas meter must be doubled or tripled, etc., in size (depending upon the number
of heaters). Example for 1/2 inch diameter supply line: If the supply line branches
to serve two heaters, the line diameter from the branch back to the gas meter must
be at least 1 inch. If three heaters are served, the line diameter from the branch
back to the gas meter must be at least 1 1/2 inches.
Note: If gas supply line total length exceeds forty feet, use a larger diameter pipe.
Use pipe that is the next size larger than the heater control valve fitting.
WARNING
A qualified service person must connect heater to gas
supply. Follow all local codes.
WARNING
Never connect heater to private (non-utility) gas wells.
This gas is commonly known as well-head gas.
IMPORTANT: Check gas line pressure at gas meter before connecting heater to gas
line. Gas line pressure must be no greater than 14 inches of water. If gas line
pressure is higher, heater regulator damage could occur.
Gas Meter
Figure 6 - Connecting Heater to Utility Gas Line
CAUTION
Use only new, black iron or steel pipe. Internally-tinned
copper tubing may be used in certain areas. Check your
local codes. Use pipe that is 1/2" in diameter or greater
to allow proper gas volume to heater. If pipe is too
small, undue loss of pressure will occur.

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100792
Figure 7 - Gas Connection
* An A.G.A. design-certified manual shutoff valve with 1/8" NPT tap is an
acceptable alternative to test gauge connection. Purchase the optional A.G.A.
design-certified manual shutoff valve from your dealer. See Accessories, page 37.
** For purposes of input adjustment.
Installation must include a manual shutoff valve, ground joint union, plugged 1/8"
NPT tap, and a sediment trap. Locate NPT tap within reach for test gauge hook up.
NPT tap must be upstream from heater (see Figure 7).
Apply pipe joint sealant lightly to male threads. This will prevent excess sealant
from going into pipe. Excess sealant in pipe could result in clogged heater valves.
INSTALLING
HEATER
Continued
Acceptable
construction
of inlet gas
line
From Gas
Meter (5" W.C.
Min** to 7"
W.C. Max)
From
Gas
Meter (5"
W.C.
Min** to
7" W.C.
Max)
Pipe
Nipple
Tee Joint
Cap
Manual
Shutoff
Valve *
Ground
Joint
Union
Tee Joint
1/8" NPT
Plug Tap
Reducer
Bushing to
1/8" NPT
Test
Gauge
Connection*
Preferred
construction
of inlet gas
line
Install sediment trap in supply line as shown in Figure 7. Locate sediment trap
where it is within reach for cleaning. Locate sediment trap where trapped matter is
not likely to freeze. A sediment trap traps moisture and contaminants. This keeps
them from going into heater controls. If sediment trap is not installed or is installed
wrong, heater may not run properly.
IMPORTANT: Use two pipe wrenches when connecting gas piping to gas control
valve of heater. This will prevent turning or damaging control valve.
CAUTION
Use pipe joint sealant that is resistant to liquid petro-
leum (LP) gas.
Sediment
Trap
Control
Valve

13
100792
INSTALLING
HEATER
Continued
CHECKING GAS CONNECTIONS
Pressure Testing Gas Supply Piping System
Test Pressures In Excess of 1/2 PSIG
1. Disconnect heater and its individual manual shutoff valve from gas supply
pipe. Pressures in excess of 1/2 PSIG will damage heater regulator.
2. Cap off open end of gas pipe where manual shutoff valve was connected.
3. Pressurize supply piping system by either using compressed air or opening
main gas valve located on or near gas meter.
4. Check all joints of gas supply piping system. Apply mixture of liquid soap and
water to gas joints. Bubbles forming show a leak.
5. Correct all leaks at once.
Test Pressures Equal To or Less Than 1/2 PSIG
1. Close manual shutoff valve (see Figure 8).
2. Pressurize supply piping system by either using compressed air or opening
main gas valve located on or near gas meter.
3. Check all joints from propane supply tank to manual shutoff valve. Apply
mixture of liquid soap and water to gas joints. Bubbles forming show a leak.
4. Correct all leaks at once.
Pressure Testing Heater Gas Connections
1. Open manual shutoff valve (see Figure 8).
2. Open main gas valve located on or near gas meter.
3. Make sure control knob of heater is in the OFF position.
4. Check all joints from manual shutoff valve to control valve on heater. Apply
mixture of liquid soap and water to gas joints. Bubbles forming show a leak.
5. Correct all leaks at once.
6. Light heater (see Operating Heater, pages 21 through 23). Check the rest of the
internal joints for leaks.
7. Turn off heater (see To Turn Off Gas to Appliance,page 23).
P
O
On Position
Off Position
Figure 8 - Manual Shutoff Valve
WARNING ICON G001
WARNING
Never use an open flame to check for a leak. Apply a
mixture of liquid soap and water to all joints. Bubbles
forming show a leak. Correct all leaks at once.
WARNING ICON G 001
WARNING
Test all gas piping and connections for leaks after install-
ing or servicing. Correct all leaks at once.
Continued

14
100792
INSTALLING
HEATER
Continued
INSTALLING RADIANTS
WARNING ICON G001
WARNING
Carefully handle the glass panel. Glass edges are
rounded and buffed to prevent cuts, however, chipped
or broken sections of glass can present sharp edges.
These sharp edges can cut skin.
1. Remove glass guard from across opening at front of heater (see Figure 8).
2. Place radiants into combustion chamber through opening at front of heater.
Front of radiant sits on front radiant support (see Figure 9, page 14). Back of
radiant rests on back radiant support (see Figures 8 and 9).
Note: Radiants should never come in contact with burner flame. Contact with
flame may cause carbon or soot deposits on radiants.
Glass
Guard
Burner
Combustion
Chamber
Back Radiant
Support
Lower Front
Access Area
Glass Retaining Channel
Lower
Front Access
Panel
Figure 10 - Position of Radiant
Radiant
Figure 9 - Location of Radiants
Back Radiant Support
Burner
Front Radiant
Support

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100792
INSTALLING
HEATER
Continued
INSTALLING GLASS PANEL
1. Locate the glass panel package inside the back of the heater.
Glass
Panel
Lower Front
Access Area
Screw
Glass
Guard
Hearth
Assembly
Figure 11 - Inserting Glass Panels
WARNING ICON G001
CAUTION
Before installing glass panels, inspect the edges. If you
notice any chips or cracks, do not install. If the surface on
either side is deeply scratched, do not install. If these
conditions exist, call DESA International’s Technical Ser-
vice Department at 1-800-323-5190 for replacement glass
panels.
WARNING ICON G 001
CAUTION
Glass panels may have sharp edges. Handle with care.
WARNING ICON G001
CAUTION
Do not operate heater without glass panels installed.
Operating heater without glass panels will damage front
of heater due to excess temperatures.
2. Remove lower front access panel of heater by removing two screws at upper
corners of panel. The lower front access panel covers the lower front access
area (see Figure 9, page 14).
3. Remove two screws on glass guard. Remove glass guard (see Figure 11).
4. Carefullyinsertoneglasspanelupthroughlowerfrontaccessarea(seeFigure11).
5. Carefully slip glass panel behind hearth assembly (see Figure 11).
Continued

16
100792
INSTALLING
HEATER
Continued
Figure 12 - Inserting Top Edge of Glass Panel into
Upper Glass Retaining Channel
WARNING ICON G 001
CAUTION
Make sure you insert top edge of glass panels into the
upper glass retaining channel. Do not install glass
panels with top edge of glass in front of the upper glass
retaining channel. Glass panels will not automatically
go into the channel. You must guide the glass panels
into it. Incorrect installation will damage front of heater
due to excess temperatures.
6. Inserttopedgeofglasspanelintotheupperglassretainingchannel(seeFigure12).
2
1
Glass
Panel
Lower Front Access Area
Upper Glass
Retaining Channel
7. Lowerglass into lower glass retaining channel. Slide glass panelall the way to the
left side.
Note: If you have chipped or cracked a glass panel during installation, do not
use. Contact DESA International’s Technical Service Department at 1-800-
323-5190 for a replacement glass panel.
2
1
Glass
Panel
Figure 13 - Inserting Glass into Lower Retaining Channel
8. Repeat steps 4 through 7 for all glass panels.
9. Reinstall glass guard. Reinstall lower front access panel of heater.
Lower Glass
Retaining Channel
Lower Glass
Retaining
Channel

17
100792
AIR FOR
COMBUSTION
AND
VENTILATION
WARNING ICON G001
WARNING
This heater must have fresh air for proper operation. If
not, poor fuel combustion and improper venting of flue
gases will result. Carbon monoxide poisoning from
backed-up flue gases could occur. Read the following
instructions to insure proper fresh air for this and other
fuel-burning appliances in your home.
Today’s homes are built more energy efficient than ever. New materials, increased
insulation, and new construction methods help reduce heat loss in homes. Home
owners weather strip and caulk around windows and doors to keep the cold air out
and the warm air in. During heating months, home owners want their homes as
airtight as possible.
While it is good to make your home energy efficient, it is not good to make it too
airtight. Your home needs to breath. If your home is too airtight, fresh air has little
chance of entering in. This could be dangerous if you have fuel-burning appliances.
These appliances need fresh, outside air for proper combustion and ventilation.
Exhaust fans, fireplaces, clothes dryers, and fuel-burning appliances draw air from
the house to operate. This heater is a fuel-burning appliance. It uses air from inside
the house for combustion. It also uses this air as a draft for venting. This draft air
helps move combustion gases through the vent pipe to the outdoors. If your house
is too airtight, there is not enough fresh air for these items to use. Fresh air may
draw back into the house through venting flues and chimneys. This will keep fuel-
burning appliances from venting properly. This may cause them to release poison-
ous carbon monoxide gas into your home. It is very important to provide enough
fresh air to run all fuel-burning appliances.
WARNING ICON G001
DANGER
Carbon monoxide poisoning may lead to death!
Carbon monoxide is a colorless, odorless gas. Early signs of carbon monoxide
poisoning resemble the flu, with headaches, dizziness, and/or nausea. If you have
these signs, the heater may not be operating or venting properly. Get fresh air at
once! Have heater or heater venting system serviced. Some people are more
affected by carbon monoxide than others. These include pregnant women, persons
with heart and lung disease and anemia, those under the influence of alcohol, and
those at high altitudes.
Continued

18
100792
AIR FOR
COMBUSTION
AND
VENTILATION
Continued
Figure 14 - Checking for Draft Spillage
No Draft Hood Spillage: This shows there is enough fresh air in area for
appliances. Turn off all exhaust fans and appliances if desired.
In the absence of local codes, use the following excerpts from the National Fuel
Gas Code NFPA 54/ANSI Z223.1, Air for Combustion and Ventilation.
DETERMINING FRESH-AIR FLOW FOR HEATER LOCATION
Example 1: Locating Heater in Unconfined (Open) Area
NOTICE
An unconfined area has a minimum air volume of 50
cubic feet for each 1000 BTU/Hr input rating of all
appliances in the area (cubic feet equals length x width
x height of area). Include adjoining rooms only if there
are no doors between the rooms or if you add ventila-
tion grills between the rooms (see Ventilating Confined
Area, page 20).
In an open area, the air that leaks around doors and windows may provide enough
fresh air for combustion and ventilation.
Draft Hood Spillage Test
Follow the steps below to see if enough fresh air is available.
1. Close all windows and doors.
2. If you have a fireplace, start a fire. Build fire until flames are burning strongly.
3. Turn on all exhaust fans. These include exhaust fans for kitchen, bathroom,
water heaters (gas or electric), etc.
4. Turn on all vented gas appliances. These include any room heaters, water
heaters, clothes dryer, etc.
5. Wait ten minutes for drafts to regulate.
6. Check for draft-hood spillage at each vented gas appliance. Do this by holding
a lit match two inches from the draft opening (see Figure 14). If match flame
pulls toward the draft hood, there is no spillage. If match flame blows away
from the draft hood, there is spillage. This is a hazardous condition. See Draft
Hood Spillage, page 19.
Typical
Water
Heater
Match
Draft Hood
Vent Pipe
Heater
Match
Draft Hood
Opening
Vent Pipe

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Continued
Figure 15 - Ventilation Air from Outdoors
IMPORTANT
Do not provide openings for inlet or outlet air into attic
if attic has a thermostat controlled power vent.
Chimney
or Gas
Vent Outlet
Air Ventilated
Attic
Outlet
Air
Inlet
Air
Inlet Air Ventilated
Crawl Space
To
Crawl
Space
To Attic
Continued
Draft Hood Spillage: This is a hazardous situation. Draft hood spillage re-
leases poisonous carbon monoxide gas into your home.
WARNINGICON G 001
DANGER
Carbon monoxide poisoning may lead to death!
If draft hood spillage occurs, check for blocked flue connectors, vent pipes, and
chimneys. If you find blockage, remove. Test again for spillage. If spillage still
occursortherewasnoblockage,youneedmorefresh,outsideairinthehouse.You
must provide additional fresh-air ventilation. Follow the steps below at once.
A. Open a window near the appliance(s) at least two inches. Test again for
spillage. If spillage does not stop, open window more and retest. If spillage
stops, keep window open while running appliance(s). Supply fresh, outside
air by a permanent method as soon as possible. If spillage still occurs, leave
window open and go to next step.
B. If you have a fireplace, open a window or door near it at least two inches.
Test again for spillage. If spillage does not stop, open window or door more
and retest. If spillage stops, keep window or door open while using fire-
place. Supply fresh, outside air by a permanent method as soon as possible.
If spillage still occurs, leave window or door open and go to next step.
C. If you have kitchen and bathroom exhaust fans, turn them off. Test again for
spillage.If spillage stops, do not use exhaustfans.Turn off circuit breakers for
fans if possible. Permanently supply fresh, outside air as soon as possible.
Providing Permanent Fresh-Air Ventilation
If draft hood spillage occurs, you must permanently supply fresh, outside air to the
inside of your house. Provide extra fresh air by using ventilation grills or ducts.
Connect these items directly to the outdoors or spaces open to the outdoors. These
spaces include attics and crawl spaces. If you install this heater in an area with
other gas appliances, you must total the BTU/Hr input rating of all appliances.
Follow the National Fuel Gas Code NFPA 54/ANSI Z223.1. It lists fresh-air
requirements for fuel-burning appliances.

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Continued
After providing ventilation between rooms, check for draft hood spillage (see Draft
Hood Spillage Test, page 18). If draft hood spillage still occurs, provide more
ventilation between rooms or provide permanent ventilation from outdoors. See
Providing Permanent Fresh-Air Ventilation, page 19.
Figure 16 - Ventilation Air from Inside Building
Example 2: Locating Heater in Confined (Closed) Area
NOTICE
A confined area has an air volume of less than 50 cubic
feet for each 1000 BTU/Hr input rating of all appliances
in the area (cubic feet equals length x width x height of
area). Include adjoining rooms only if there are no doors
between the rooms.
If you install this heater in a confined area, you must provide additional fresh air.
Ventilating Confined Area
This fresh air would come from an adjoining open area or outdoors.
WARNING ICON G001
WARNING
The adjoining open area must have enough fresh,
outside air ventilation to supply any appliance in that
area plus the confined area. Follow instructions under
Example 1: Locating Heater in Unconfined (Open) Area,
page 18 to make sure fresh air ventilation is adequate.
When ventilating to an adjoining open area, you must provide two permanent
openings: one within 12" of the ceiling and one within 12" of the floor on the wall
connecting the two areas. Follow the National Fuel Gas Code NFPA 54/ANSI
Z223.1. It lists fresh-air requirements for fuel-burning appliances.
Ventilation
Grills into
Closet for
Hot Water
Heater
Recommended
Fresh Air Duct
into Crawl Space in
Furnace Area or in
Closet with Water Heater
Ventilation Grills
Connecting Two Rooms
to Meet Unconfined Space
12"
12"