Johnson Controls Unitary Products
129098-UIM-G-0411
For Installation In:
1.
Manufactured (Mobile) Homes
2.
Recreational Vehicles & Park Models
3.
Modular Homes & Buildings
HIGH EFFICIENCY
SEALED COMBUSTION GAS FURNACE
MODELS: DGAA and DGAH
(Single Stage Downflow Only)
56 - 90 MBH INPUT
(16.41 - 26.38 KW) INPUT
INSTALLATION MANUAL
LIST OF SECTIONS
SAFETY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
DUCTWORK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
RETURN AIR REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
FILTERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
GAS LINE INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
ELECTRICAL POWER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
ROOF JACK VENT/COMBUSTION AIR SYSTEM . . . . . . . . . . . . . 13
SAFETY CONTROLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
START-UP AND ADJUSTMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . 20
WIRING DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
LIST OF FIGURES
Furnace Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Air Distribution Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Closet To Door Clearance - 5” or Greater . . . . . . . . . . . . . . . . . . . . . . 5
Furnace To Closet Door Clearance - 1” To 5” . . . . . . . . . . . . . . . . . . . 6
Furnace To Closet Door Clearance - Less Than 1” . . . . . . . . . . . . . . . 6
Duct Connector Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Recommended Floor Cut-out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Duct Connector Depth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Duct Connector Screw Attachment . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Duct Connector Tab Attachment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Anti-Backflow Damper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Floor Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Furnace Air Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Gas Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Burner Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Line Wiring Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Wiring for Heat Only Thermostat . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Wiring for Electronic Heat-Cool Thermostat . . . . . . . . . . . . . . . . . . . 13
Wiring for Standard Heat-Cool Thermostat . . . . . . . . . . . . . . . . . . . 13
Wiring for Blend Air Accessory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Standard Roof Jack . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Roof Jack With Removable Crowns . . . . . . . . . . . . . . . . . . . . . . . . . 16
Roof Jack . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Connecting Roof Jack to Furnace . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Roof Jack Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Ceiling Rings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Home Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Pressure Switch Tubing Routing . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Gas Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Reading Gas Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Furnace Control Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Wiring Diagram - DGAA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Wiring Diagram - DGAH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
LIST OF TABLES
Unit Clearances to Combustibles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
External Static Pressure Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Filter Sizes - All Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
High Altitude Duration Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Ratings & Physical / Electrical Data . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Roof Jack Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Inlet Gas Pressure Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Nominal Manifold Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Blower Performance CFM - Downflow Without Filters . . . . . . . . . . . 25
AC Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
SECTION I: SAFETY
This is a safety alert symbol. When you see this symbol on
labels or in manuals, be alert to the potential for personal
injury.
Understand and pay particular attention to the signal words
DANGER
,
WARNING
, or
CAUTION
.
DANGER
indicates an
imminently
hazardous situation, which, if not
avoided,
will result in death or serious injury
.
WARNING
indicates a
potentially
hazardous situation, which, if not
avoided,
could result in death or serious injury
.
CAUTION
indicates a potentially hazardous situation, which, if not
avoided
may result in minor or moderate injury.
It is also used to
alert against unsafe practices and hazards involving only property dam-
age.
Improper installation may create a condition where the operation of
the product could cause personal injury or property damage.
Improper installation, adjustment, alteration, service or mainte-
nance can cause injury or property damage. Refer to this manual
for assistance or for additional information, consult a qualified con-
tractor, installer or service agency.
This product must be installed in strict compliance with the installa-
tion instructions and any applicable local, state, and national codes
including, but not limited to building, electrical, and mechanical
codes.
