Operating Instructions for Mr. Heater MH140CKT, MH185CKT, and MH220CKT Kerosene Forced-Air Heaters

Important Information

This manual provides operating instructions for the Mr. Heater MH140CKT, MH185CKT, and MH220CKT kerosene forced-air heaters. These units are intended for temporary heating of buildings under construction, alteration, or repair. They are not for home or recreational vehicle use.

Safety Warnings:

• Never leave the heater unattended while burning.
• Do not use gasoline, naphtha, or volatile fuels.
• Always operate in well-ventilated areas. Inadequate ventilation can lead to carbon monoxide poisoning.
• Keep combustibles (paper, wood, canvas, plastic) at least 8 ft. from the outlet and 3 ft. from the sides and inlet.
• Do not use in areas where flammable liquids or vapors are present.
• Plug into a properly grounded three-prong receptacle.

Specifications

The heaters are factory tested for No. 1-K kerosene, No. 2-K kerosene, No. 1 or No. 2 Diesel, No. 1 or No. 2 fuel oil, JP8 Jet A fuel, and Biodiesel blends B2, B5, B10, and B20. CSA certified for use with No. 1-K kerosene only.

• MH140CKT: 140,000 Btu/hr, 8-gallon tank.
• MH185CKT: 185,000 Btu/hr, 13-gallon tank.
• MH220CKT: 220,000 Btu/hr, 13-gallon tank.
• Electrical: 115V, 60Hz.

Assembly

The heater comes with wheels, axle, and handles in the shipping carton.

1. Handles are pre-assembled on the tank.
2. Install one large lock nut onto the end of the axle.
3. Slide one wheel onto the axle, then one spacer.
4. Slide the axle through the wheel support frame.
5. Slide the second spacer, then the second wheel, and finally the second large lock nut onto the axle.
6. Tighten both nuts using two adjustable wrenches. Do not overtighten.

Operation

Start-Up:

1. Turn the thermostat to the lowest setting and ensure the On/Off switch is in the "Off" position.
2. Plug the heater into a grounded 115V outlet.
3. Turn the thermostat to the highest setting.
4. Push the toggle switch to "On".
5. Adjust the thermostat to the desired setting. The heater will cycle on/off as needed.

Shut Down:

• Push the On/Off switch to "Off". For extended shutdown, unplug the heater.

Maintenance and Storage

Periodic maintenance is required for efficient operation.

• Pump Pressure Adjustment: If the flame is inconsistent or smokes, the pump pressure may need adjustment. Locate the pressure adjustment screw on the rear of the heater. Use a flat-head screwdriver to turn clockwise to increase pressure or counter-clockwise to decrease pressure.
• Cleaning: Clean air intake filters, remove dust from the burner/fan area, and clean the cad cell eye regularly.
• Storage: Store in a dry location. Drain and flush the fuel tank with clean fuel before long-term storage.

Troubleshooting

If the heater fails to operate, check the following:

• Heater shuts off: Ensure the unit is cool, toggle switch to "Off", wait 5 minutes, and retry.
• No spark: Check extension cord requirements, wiring to the ignition electrode, and the electrode gap (3.5 mm).
• Abnormal motor operation: Ensure the fan rotates freely; if not, the motor or power-pack may need replacement.
• Unable to detect flame: Clean the cad cell eye with a soft cloth and rubbing alcohol.