User Manual for Stelpro Oxford Series Agricultural Unit Heater

Quick guide from the manual

This manual covers the installation, operation, and maintenance of the Stelpro Oxford Series agricultural unit heaters. Key safety requirements include installing the unit at a minimum height of 6 ft (1.83 m) and a maximum of 10 ft (3 m) from the floor. Ensure a minimum clearance of 24 in. (60 cm) under the unit and 6 in. (15 cm) on each side to prevent overheating. The unit must be installed by a certified electrician in accordance with local electrical and building codes.

Installation

The unit and bracket weigh 35 lbs (16 kg). Ensure the mounting surface can support this weight. Use a stud finder to locate ceiling or wall studs for secure mounting. The mounting bracket must be attached to a stud. Follow the specific diagrams provided for wall or ceiling installation options. Ensure the bracket is level before attaching the heater.

Electrical Connection

Before connecting, turn off the power supply at the electrical panel. Open the junction box cover by unscrewing the two screws. Remove the protective cap to unblock the opening for power cables. Install a sealed connector (not included) and insert the power cables, leaving 6 in. (15 cm) of wire inside the junction box. Connect the power supply and thermostat wires according to the specific circuit diagram for your model (with or without built-in thermostat). Ensure all terminal screws are tightened firmly.

Operation

The unit features a main switch to turn off power supply. Models SFH0521TDIS and SFHGX0521TDIS include a built-in thermostat for temperature control. Model SFH0521DIS requires an external wall line volt thermostat. An operation mode selector switch allows choosing between Ventilation only mode or Ventilation and heating mode. The unit includes a time-delay feature to cool heating elements after the setpoint is reached.

Maintenance

Regular cleaning of the air inlet and outlet is required for warranty validity. Turn off power at the electrical panel before cleaning. Dust the unit with a soft cloth or use a vacuum cleaner with a dust brush in dusty areas. The unit is water-resistant and can be hosed down. Never use metal brushes, scouring pads, chlorine, abrasive cleaning products, or hydrochloric-acid based products.

Troubleshooting

If the unit does not start, check the setpoint, wiring connections, and ensure the circuit breaker and main switch are ON. If the circuit breaker trips, verify wiring and ensure the breaker/fuse is adequate for the power required. If the unit is not heating, check for obstructions at the air inlet/outlet and ensure the thermal protection has not been triggered. For model SFHGX0521TDIS, refer to the thermal protection reset procedure if overheating occurs.