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Bryant Furnace Code 24: Low-voltage fuse is open

Bryant furnace code 24 means the secondary-voltage fuse is open because of a low-voltage short on the supported control family. Confirm the model number and diagnostic chart inside the furnace door before replacing parts.

Reviewed August 2026
Furnace control · fault
24
Low-voltage fuse
BRYANTTwo-digit LED codes similar to Carrier, e.g. 23 or 33

What does Bryant code 24 mean?

Bryant furnace code 24 means the secondary-voltage fuse is open because of a low-voltage short on the supported control family. Confirm the model number and diagnostic chart inside the furnace door before replacing parts.

What causes Bryant code 24?

  • Shorted thermostat wiring
  • A shorted low-voltage accessory
  • A damaged control-board circuit

Can I troubleshoot Bryant code 24?

  1. Turn furnace power off and check for an obviously pinched thermostat wire without touching board terminals.
  2. Do not install a larger fuse or repeatedly replace a fuse that opens again.

How much does Bryant code 24 cost to fix?

A control board replacement typically costs between $150 and $600 nationally.

Typical repair cost
$150$600control board replacement
Where the money goes
Part $100$350Labor $0$500Typical labor time: 1–2 hrs

When should I call a technician?

Call a technician to locate the low-voltage short before replacing the fuse again.

Symptoms this code causes

Sources and model scope

Fault codes vary by model and control board. Confirm the diagnostic chart inside your furnace panel or the official manual before acting.

Scope used here: Carrier-family two-stage controls covered by troubleshooting guide 58-3T.

Compiled by Warmlo Editorial · Reviewed August 2026

This is general information, not professional advice. Gas, electrical, and combustion repairs can be dangerous — when in doubt, call a licensed technician.