National Comfort Products CPG U-Model Non Condensing Furnace User Manual

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National Comfort Products CPG U-Model Non-Condensing Furnace Manual

Introduction to the National Comfort Products CPG U-Model Furnace

The national comfort products CPG U-Model Non Condensing Furnace is a self-contained gas-heating system designed for through-the-wall Comfort Pack applications. It combines a slide-out furnace chassis with integrated electric cooling equipment, allowing qualified installers to service major components from an accessible configuration.

This non-condensing furnace uses an approximately 80% thermal-efficiency heat exchanger and direct-spark ignition. Depending on the exact model, heating input and output vary, with listed configurations reaching up to 64,000 BTUH input and approximately 51,000 BTUH output. The furnace is available with a universal chassis and can be paired with compatible cooling sections in several capacity options.

Key features include a sealed combustion chamber, a single gas orifice design, diagnostic LEDs visible through the furnace access door, and a sight glass for observing flame and diagnostic activity. A five-speed DC indoor blower motor supports airflow adjustment for different installation requirements.

This furnace is intended for properly sized residential, manufactured-housing, light-commercial, and replacement applications where a through-the-wall heating and cooling package is appropriate. It is best suited to homeowners, property managers, and HVAC professionals who need a compact, serviceable gas furnace rather than a high-efficiency condensing system.

Installation, gas conversion, electrical connections, combustion checks, and commissioning must be completed by qualified HVAC personnel in accordance with the unit documentation and applicable local codes.

Specifications and Features

Product type: Self-contained Comfort Pack gas heating and electric cooling unit.
Furnace design: Non-condensing, slide-out gas furnace chassis.
Nominal thermal efficiency: Approximately 80% for listed non-condensing configurations.
Heating input options: Model-dependent configurations include approximately 28,000, 38,000, 51,000, and 64,000 BTUH input.
Heating output: Up to approximately 51,000 BTUH, depending on the selected model.
Ignition: Direct-spark ignition with a single gas-orifice arrangement.
Heat exchanger: Slide-out furnace assembly with a 409 stainless-steel heat exchanger in listed non-condensing specifications.
Combustion system: Sealed combustion chamber for the intended through-the-wall application.
Blower motor: Adjustable five-speed DC indoor motor.
Cooling compatibility: Compatible model families include electric cooling capacities such as 1, 1.5, 2, and 2.5 tons, depending on the complete unit configuration.
Filter: A 16-by-25-inch filter is included with listed standard configurations; verify the label and installation manual for the exact filter arrangement.
Diagnostics: Furnace-door diagnostic LEDs and a sight glass for flame observation.
Gas supply: Verify the required fuel type and pressure on the appliance rating plate before installation. Do not adjust gas pressure without qualified service equipment.

Setup Guide: How to Install and Configure the CPG U-Model Furnace

Important: Installation must be performed by a qualified HVAC technician. Shut off electrical power and the gas supply before servicing. Never operate the furnace with panels removed, blocked airflow, damaged wiring, or suspected gas leakage.

Confirm the complete model number, fuel type, heating input, electrical rating, and installation clearances from the rating plate and exact unit manual.
Inspect the wall opening, mounting surface, exterior grille, cabinet, and chassis for shipping damage. Confirm that the unit is suitable for the intended through-the-wall installation.
Position and secure the cabinet according to the manufacturer’s dimensional and clearance requirements. Do not modify the cabinet or grille without written approval.
Connect the properly sized gas supply, manual shutoff valve, sediment protection, and approved piping. Test all joints for leakage using an approved method; never use an open flame.
Connect line-voltage wiring, grounding, thermostat wiring, and any compatible cooling controls according to the wiring diagram inside the unit.
Install the correct filter and verify that return and supply air paths are unobstructed. Select the blower speed appropriate for the system airflow and cooling configuration.
Open the gas valve, restore power, set the thermostat to call for heat, and observe the ignition sequence. Confirm stable flame, correct airflow, safe temperature rise, and proper limit operation.
If the burner does not ignite, check the thermostat call, service switch, gas valve position, diagnostic LEDs, wiring, and airflow. Stop immediately if gas odor or abnormal combustion is detected.

Troubleshooting the National Comfort Products CPG U-Model Non Condensing Furnace

Diagnostic lights should be interpreted using the exact wiring diagram and service instructions supplied with the furnace. LED patterns and controls can vary by production version, so do not assign an error meaning from a different model.

No heat or no response: Check thermostat settings, the electrical disconnect, circuit protection, service switch, and low-voltage connections. A qualified technician should verify control voltage.
Igniter operates but burner will not light: Confirm that the manual gas valve is open and that the fuel supply is available. Air in a new gas line, incorrect pressure, damaged ignition wiring, poor grounding, or a defective gas valve can prevent ignition.
Burner lights and then shuts off: Have a technician inspect flame sensing, grounding, burner alignment, combustion air, venting, and control-board diagnostics.
Repeated limit trips: Replace a blocked or dirty filter, check supply and return restrictions, verify blower operation and speed, and confirm that registers are open. Do not bypass a safety limit.
Weak airflow: Inspect the filter, blower wheel, motor setting, duct restrictions, and cooling-chassis connections.
Blower does not run: Check the thermostat fan request and control wiring. A technician should test the motor, capacitor or control components where applicable, and board outputs.
Gas odor or soot: Turn off the gas supply if safe, leave the area, avoid switches and flames, and contact the gas supplier or emergency service. Do not restart the furnace.

Preventive maintenance includes replacing the filter as needed, keeping outdoor grilles clear, inspecting wiring and combustion components, and scheduling professional annual service. For warranty questions, parts, manuals, or model-specific diagnostics, use the model and serial numbers when contacting National Comfort Products or an authorized HVAC dealer. Contact information should be taken from the product rating plate, official documentation, or the manufacturer’s current support channel.

Pros and Cons of the CPG U-Model Furnace

Advantages

Serviceable design: The slide-out furnace chassis can simplify access for qualified technicians compared with permanently fixed furnace compartments.
Integrated system: A compatible heating and cooling package can provide a compact alternative to separate indoor HVAC equipment.
Practical diagnostics: Door-visible LEDs and a sight glass help technicians evaluate ignition and flame conditions.
Flexible airflow: Five blower-speed settings support adjustment for different duct and cooling requirements.
Reliable ignition approach: Direct-spark ignition avoids the need for a continuously burning pilot light.
Broad application range: Multiple heating capacities allow qualified professionals to match the unit more closely to the building load.

Limitations

Lower efficiency than condensing furnaces: The approximately 80% design does not provide the fuel efficiency of modern high-efficiency condensing equipment.
Installation-specific: The through-the-wall configuration and cabinet requirements may not suit conventional basement, attic, or closet installations.
Professional service required: Gas pressure, combustion, ignition, and safety controls require specialized tools and training.
Model differences matter: Heating capacity, cooling capacity, filter arrangement, and controls vary by complete model number.

The national comfort products CPG U-Model Non Condensing Furnace is a strong fit for compatible through-the-wall Comfort Pack replacements and compact packaged HVAC applications. Buildings requiring the lowest possible fuel use, extensive zoning, or a conventional indoor furnace layout may be better served by another equipment category.

Frequently Asked Questions

What type of furnace is the CPG U-Model?

It is a gas-fired, non-condensing furnace integrated into a Comfort Pack heating and cooling system. The exact heating capacity depends on the model number.

Is the CPG U-Model a condensing furnace?

No. The non-condensing versions use an approximately 80% thermal-efficiency design and should not be confused with National Comfort Products condensing models.

Can a homeowner install this furnace?

Gas, electrical, venting, combustion, and safety work should be completed by a qualified HVAC professional. Improper installation can create fire, explosion, carbon-monoxide, electrical, or equipment hazards.

How often should the filter be changed?

Inspect the filter regularly and replace it when loaded with dust or when airflow is reduced. The correct replacement interval depends on occupancy, pets, indoor air quality, and filter type.

Where can the exact specifications be found?

Use the complete model and serial numbers on the rating plate, then consult the matching installation manual and specification sheet. The model number determines heating input, cooling capacity, options, and electrical requirements.

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Faqs

How do I set up the National Comfort Products CPG U-Model Non Condensing Furnace for the first time?

The National Comfort Products CPG U-Model Non Condensing Furnace is designed for qualified installation in an outside wall for through-the-wall use. A licensed installer should verify the wall opening, clearances, venting, gas piping, electrical connections, condensate-free drainage, thermostat wiring, and local code requirements. Before operation, the installer should test for gas leaks, confirm proper burner ignition, check airflow, and verify that the thermostat starts and stops heating correctly.

What should I check if my National Comfort Products CPG U-Model Non Condensing Furnace will not start?

First, confirm that the thermostat is set to heat, the temperature setting is above room temperature, and the thermostat has power. Check whether the furnace service switch and circuit breaker are on, and verify that the manual gas valve is open. Do not repeatedly reset the furnace if it fails to ignite. If the unit still does not start, contact a qualified HVAC technician to inspect the ignition system, safety controls, wiring, and gas supply.

Why does the National Comfort Products CPG U-Model Non Condensing Furnace run but produce little heat?

Restricted airflow is a common cause of weak heating. Replace or clean the air filter according to its condition, and make sure supply registers and return-air openings are not blocked. Check that the blower operates normally and that the thermostat is not affected by drafts or nearby heat sources. If airflow is adequate but the air remains cool, stop operating the furnace and arrange professional service for burner ignition, gas pressure, heat exchanger, and limit-control checks.

Can the National Comfort Products CPG U-Model Non Condensing Furnace be installed in any room or wall?

No. The National Comfort Products CPG U-Model Non Condensing Furnace is intended for outside-wall, through-the-wall installation rather than unrestricted indoor placement. The installation location must provide the clearances, combustion-air conditions, vent termination space, service access, and structural support specified for the exact model. Never install the furnace in a closet, interior wall, or confined space unless the model documentation and local codes specifically permit that arrangement.

How can I improve airflow and heating performance on a National Comfort Products CPG U-Model Non Condensing Furnace?

Use the correct filter size and replace it when visibly dirty or when airflow decreases. Keep return grilles, supply registers, and the outdoor wall area clear of furniture, dust, snow, and other obstructions. Make sure doors and grilles allow air to move freely through the space. Avoid closing many registers, because this can reduce airflow and trigger overheating limits. Persistent short cycling or uneven heat requires professional duct, blower, and control inspection.

What thermostat and electrical requirements should I confirm before installing the National Comfort Products CPG U-Model Non Condensing Furnace?

Use only a thermostat and wiring arrangement approved for the exact CPG U-Model configuration, since some Comfort Pack units combine gas heating with electric cooling. The installer should compare the unit wiring diagram with the thermostat terminals, confirm the required power supply, protect the circuit properly, and verify grounding. Turn off electrical power before accessing wiring. Do not connect accessories or change control wiring without guidance from the installation manual or a qualified technician.

How often should I maintain the National Comfort Products CPG U-Model Non Condensing Furnace?

Inspect the filter regularly and replace it whenever it becomes dirty or restricts airflow. Arrange professional furnace maintenance at least annually, preferably before the heating season. Service should include burner and ignition inspection, heat exchanger examination, blower and electrical checks, safety-control testing, vent inspection, and gas-leak testing. Keep the cabinet and surrounding area clean and unobstructed. Because this is a gas appliance, do not remove or adjust combustion components yourself.

What should I do if the National Comfort Products CPG U-Model Non Condensing Furnace makes unusual noises or smells like gas?

Turn the thermostat off and note whether the sound occurs during ignition, blower operation, or shutdown. Rattling may indicate a loose panel, while scraping or humming can require blower inspection. A brief dusty odor at the beginning of a season may come from dust, but a gas smell is an emergency: do not operate switches, use flames, or remain near the appliance. Leave the area, contact the gas supplier or emergency services, and have the furnace professionally inspected.