1. Manuals
  2. Brands
  3. MORTEX Manuals
  4. Furnace
  5. G18D SERIES
  6. Installation manual

MORTEX G18D Series Installation Manual

Downflow only gas furnace
Hide thumbs Also See for G18D Series:
Table of Contents

Advertisement

Quick Links

Download this manual
DOWNFLOW ONLY GAS FURNACE
SIZES 60, 70, 77, 90
MODELS: G18D SERIES
For installation only in HUD manufactured homes per Construction Safety 24 CFR Part 3280
1 - Safety .....................................................................................................................2
2 - General Information ........................................................................................6
3 - Furnace Ductwork and Filters ......................................................................8
4 - Gas Supply and Valve Connections ......................................................... 11
5 - Line and Low Voltage Wiring ..................................................................... 17
1 - Furnace Dimensions .........................................................................................6
2 - Combustible Floor Base Assembly ..............................................................9
3 - Duct Connector Dimensions .........................................................................9
4 - Duct Connector and Floor Base Assembly ...............................................9
5 - Duct Connector Depths ..................................................................................9
6 - Air Distribution System - Single Trunk Duct ....................................... 10
7 - Air Distribution System - Double Trunk Duct ................................................ 10
8 - Air Distribution Systems - Graduated trunk duct ........................................ 10
10 - Outdoor Fresh Air Intake Knockout ......................................................... 11
12 - White Rodgers Gas valve ................................. ........................................... 12
13 - Burner Assembly................................ ............................................................ 13
14 - Component Locations................................. ................................................. 17
1 - Model Number Nomenclature ...........................................................................
................................................................................... 15
Manufactured and Distributed by:
The following list includes important facts and information regarding this gas furnace.
1. Furnace is rated at 115 VAC at 60 Hz.
2. Furnace is available in "Heating Only" or "A/C Ready" configurations.
3. Furnace is designed for use with cooling only or heat pump systems when a cooling coil cabinet and indoor coil is used. A/C
ready models are furnished with a cooling coil cabinet. The appropriate indoor coil must be selected and ordered separately.
4. A hold-down strap is furnished with furnace.
5. This furnace is designed for downflow applications only.
6. This furnace must not be operated with the control box cover or front access panels removed.
7. This furnace is certified by ETL for use in the United States only.
MORTEX PRODUCTS INC
INSTALLATION MANUAL
LIST OF SECTIONS
LIST OF FIGURES
LIST OF TABLES
............................................................7
........................................................... 14
............................................................... 16
......................................... 16
........................ 16
............................ 16
................................ 18
CONTACT INFORMATION
Mortex Products Inc
501 Terminal Rd
Fort Worth, TX 76106
SAVE THIS MANUAL FOR FUTURE REFERENCE
501 TERMINAL RD FORT WORTH, TX 76106
6 - Furnace Combustion Air and Vent System ............................................20
8 - Blower Performance ......................................................................................31
9 - Wiring Diagrams .............................................................................................32
20 - Roof Jack Mounting Collars - Top of Furnace .....................................21
21 - Roof Jack Indoor Extension Pipes ...........................................................21
22 - Roof Jack Outdoor Extension Pipes.........................................................21
23 - Roof Jack Slope Saddle ................................................................................22
24 - Roof Jack Crown Assembly ........................................................................22
25 - Combustion Air Path Through Furnace Casing ...................................23
26 - Flue Vent & Combustion Air For Furnace ...............................................23
27 - Home Layout & Vent Clearances ..............................................................24
28 - Typical Roof Jack Installation .....................................................................25
29 - White Rodgers Gas Valve .............................................................................27
30 - Measuring Inlet (Supply) Gas Pressure ...................................................27
31 - Measuring Outlet (Manifold) Gas Pressure ...........................................27
32 - Integrated Control Board ............................................................................29
33 - Wiring Diagram Heating Only Models....................................................32
34 - Wiring Diagram A/C Ready Models .........................................................33
6
....................................................................................................
................................................................................ 25
............................................................... 27
........................................................................... 27
.......................................... 28
....................................... 28
............................................................................ 31
www.mortx.com
20
24
.............. 29
Page 1

Advertisement

Table of Contents
loading
Need help?

Need help?

Do you have a question about the G18D Series and is the answer not in the manual?

Questions and answers

Related Manuals for MORTEX G18D Series

Summary of Contents for MORTEX G18D Series

  • Page 1: Table Of Contents

    INSTALLATION MANUAL DOWNFLOW ONLY GAS FURNACE SIZES 60, 70, 77, 90 MODELS: G18D SERIES For installation only in HUD manufactured homes per Construction Safety 24 CFR Part 3280 LIST OF SECTIONS 1 – Safety ........................2 6 – Furnace Combustion Air and Vent System ..........20 2 –...

  • Page 2: Safety

    14. Verify the supply voltage to the furnace that is shown on the data plate is not 10% lower or greater than the rated voltage. 15. Manufactured (Mobile) Home Definition: Factory-built home constructed, transported and installed under the federal MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 2...
  • Page 3 9. Check the data plate and the power supply to be sure that the electrical characteristics match. All models use nominal 115 MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 3...
  • Page 4 2. Soap powders, bleaches, waxes, or other cleaning compounds 3. Plastic items or containers 4. Gasoline, kerosene, cigarette lighter fluid, dry cleaning fluids, or other volatile fluids 5. Paper bags, boxes, or other paper products MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 4...
  • Page 5 5. Do not attempt to reuse any mechanical or electronic ignition control that has been wet. Replace a defective ignition control. 6. Servicing or repairing of this furnace must be performed by a qualified service agency. MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 5...

  • Page 6: General Information

    A/C Ready Models: 51.852” + 25.5” = 77.352” Furnace Weights Heating Only Models: 152 lbs (68.95 kg) A/C Ready Models: 175 lbs (79.38 kg) Figure 1: Furnace Dimensions MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 6...

  • Page 7: Furnace Clearances To Combustibles

    Table 2: Clearances to Combustibles Applications where the return air temperature is consistently below 55°F (13°C) may result in premature heat exchanger failure, fire, property damage, personal injury, or death. MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 7...

  • Page 8: Furnace Ductwork And Filters

    Undersized ducts can result in an abnormally high the provisions of 248 CMR 5.08(2)(a)1 through 4. temperature rise and heat exchanger overheating which can cause premature heat exchanger failure, property damage, personal injury, or death. MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 8...

  • Page 9: Combustible Floor Base Assembly

    The transition duct must have insulation between the duct and any combustible material. The transition duct must match the supply air opening dimensions of the furnace base. Figure 5: Duct Connector Depth MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 9...

  • Page 10: Air Distribution System - Single Trunk Duct

    400 ft/min (121.92 the floor for the refrigerant tubing and the electrical wiring, m/minute). thermostat wiring, and outdoor unit control wiring are in place. Install the furnace as follows: MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 10...

  • Page 11: Gas Supply And Valve Connections

    Refer to Figure 10 for damage and loss of life. knockout and screw hole locations. MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 11...

  • Page 12: Top Cover Screws And Combustion Air Pan Screws

    0.3" W.C. (0.075 kPa) has been subtracted. If 0.3" W.C. (0.075 kPa) pressure drop is too high, refer to the Gas Engineer’s Handbook for other gas pipe capacities. MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 12...

  • Page 13: Burner Assembly

    12. Reconnect the gas supply piping to the gas valve. IMPORTANT: Place the wrench only on the gas valve wrench boss when tightening the gas supply piping. MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 13...

  • Page 14: High Altitude Gas Orifice Size Chart

    72AG-0935 0.0935 9000 72AG-076 0.076 72AG-081 0.081 72AG-082 0.082 72AG-089 0.089 10000 72AG-073 0.073 72AG-078 0.078 72AG-081 0.081 72AG-089 0.089 Table 3: High Altitude Gas Orifice Size Chart MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 14...

  • Page 15: Supply Gas Pipe Sizing

    NOTE: Capability up to 14” W.C. (0.50 PSI (3.48 kPa)) gas pressure through Schedule 40 Pipe Pressure drop of 0.3” W C (0.0075 kPa) Natural Gas – Specific Gravity – 0.60; Propane Gas – Specific Gravity – 1.50 MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 15...

  • Page 16: Ratings, Physical & Electrical Data

    G18D090CA4BC Blower Motor HP Blower Motor Speeds Blower Motor FLA Nominal Air Flow 1,700 1,700 1,700 1,700 Table 8: A/C Ready Tall Cabinet Models Blower and Motor Data MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 16...

  • Page 17: Line And Low Voltage Wiring

    Homeowners and users should never attempt to perform any maintenance which requires opening the furnace control box cover. Refer to Figure 14 for the location of the ON/OFF switch. MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 17...

  • Page 18: Low Volt. Connections - Separate T'stats, Single T'fmr - A/C

    3 amp fuse. for Furnace & Condensing Unit Separate Heating and Cooling Thermostats If the heating/cooling system is a central heating and cooling MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 18...

  • Page 19: Low Volt. Connections - Single T'stat, Separate T'fmrs - A/C

    THERMOSTAT Heat Pump OUTDOOR SECTION Figure 19: Low Voltage Connections - Single Thermostat and Separate Transformers for Furnace and Heat Pump MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 19...

  • Page 20: Furnace Combustion Air And Vent System

    The installer must change the roof jack vent system when The direct venting system must be installed in accordance with installing a new furnace or replacing an existing furnace. MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 20...

  • Page 21: Roof Jack Mounting Collars - Top Of Furnace

    Permanently seal all accessories parts list in the Service and Maintenance Manual. gaps in the wall adjacent to the vent terminal. MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 21...

  • Page 22: Roof Jack Slope Saddle

    3. Align the roof jack inner and outer pipes so the pipes line up with the inner and outer collars on the top of the furnace. MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 22...

  • Page 23: Combustion Air Path Through Furnace Casing

    The vent must extend high enough above building or a neighboring obstruction so that wind from any direction will not create a positive pressure in the vicinity of the vent. MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 23...

  • Page 24: Home Layout & Vent Clearances

    Fitted with cap accordance with the vent manufacturer’s Installation Manual. installation instructions b. Or in accordance with the installation instructions for a special venting system. MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 24...

  • Page 25: Typical Roof Jack Installation

    63” – 99” 3/12 119” – 155” 140 ½” – 176 ½” Part # Roof Jack Crown MUST USE WITH ROOF JACK BODY 90-RJCRWN-AL Table 12: Roof Jack Specifications MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 25...

  • Page 26: Furnace Startup, Diagnostics And Sequence Of Operation

    Refer to the Normal Heating Mode Sequence on page 30 of these instructions for additional details. CHECKING AND ADJUSTING THE GAS INLET PRESSURE 1. Follow the procedure for “Shutting The Furnace Off” located MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 26...

  • Page 27: White Rodgers Gas Valve

    6. Turn the switch on the gas valve to the “OFF” position. BTU/cu. ft. or Mj/m³ = heating value of gas 7. Remove the pressure hose from the pressure port and tighten the set screw. MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 27...

  • Page 28: Input Calculations For Cubic Foot Gas Meters

    (1.83 m) from the furnace. The temperature rise can be changed by increasing the blower speed to reduce the temperature rise or blower. reducing the blower speed to increase the temperature rise. MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 28...

  • Page 29: Integrated Control Board

    Flame Sense Current Normal flame sense current is approximately 2.8 micro amps DC. Minimum flame sense current threshold is 0.5 micro amps DC. Figure 32: Integrated Furnace Control Board MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 29...
  • Page 30 The control board will then attempt an ignition cycle energize the induced draft blower for the post-purge period and beginning with the pressure switch check. de-energize all outputs. MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 30...

  • Page 31: Blower Performance

    1227 1166 1035 1021 Table18: Blower Performance Chart – With Filters – Without Cooling Coil * Speed tap T4 should only be used for the constant circulation mode. MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 31...

  • Page 32: Wiring Diagrams

    Figure 33: Wiring Diagram – Heating Only Models NOTE: If any of the original wires supplied with this furnace must be replaced, replace with Type 105°C thermoplastic or equivalent wire. MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106...

  • Page 33: Wiring Diagram A/C Ready Models

    Figure 34: Wiring Diagram – A/C Ready Models NOTE: If any of the original wires supplied with this furnace must be replaced, replace with Type 105°C thermoplastic or equivalent wire. MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 33...
  • Page 34 Subject to change without notice 61GF0100F Copyright by Mortex Products Inc. 2023 Supersedes: 61GF0100E MORTEX PRODUCTS INC 501 TERMINAL RD FORT WORTH, TX 76106 Page 34...

Table of Contents