Canarm - Fuse Holder for Heated Waterer

The Canarm HLW-27 fuse holder is designed for a standard automotive-style blade fuse (also called ATO/ATC fuse). The correct fuse rating depends on your waterer's wattage:

• H50 / 300W waterer: Typically a 5A fuse on the 120V control circuit
• H100 / 500W waterer: Typically a 5A fuse on the 120V control circuit

Always verify the correct fuse rating on the data plate or in the installation manual for your specific model before replacing. Never substitute a higher-amperage fuse — oversizing a fuse defeats its protective purpose and creates a fire hazard.

Replacement blade fuses are available at any automotive parts store, hardware store, or farm supply outlet. They are a standard item.

A blown fuse in the Canarm HLW-27 holder indicates an electrical overcurrent event in the waterer's control circuit. Common causes:

• Short circuit in the wiring: Damaged insulation (often from rodent chewing) can allow two conductors to contact, blowing the fuse immediately upon power-up.
• Failed thermostat drawing excess current: A shorted thermostat can draw more current than the circuit is rated for.
• Water intrusion: Moisture inside the control box can create a ground path, tripping the fuse or GFCI.
• Transient voltage spike: A lightning strike or utility power event can blow fuses throughout the barn.

Important: If the replacement fuse blows immediately or within minutes of installation, do not keep replacing fuses — there is an underlying fault that must be identified and repaired first. Repeated fuse replacement without diagnosing the root cause can result in wiring damage or fire.