Rheem Error Code 30: Open fuse (Furnace)

Updated October 15, 2026 · by Aurora Star Tech Inc.

Rheem error code 30 on a furnace means: Open fuse. It is also called Rheem diagnostic code 30.

Critical severityFurnaceR96V/96MDV

Homeowner? What Rheem code 30 means for you

Stop and call Your furnace is reporting: Open fuse. This code is a safety shutdown. Turn the furnace off and call a licensed technician. Do not keep resetting it. If you smell gas, leave the house and call your gas utility or 911 from outside.

Safe things you can check yourself

Check the thermostat: right mode (Heat or Cool), set a few degrees past room temperature, and fresh batteries if it uses them.
Make sure the unit has power: its on/off switch (often looks like a light switch near the unit) is ON and the breaker in the electrical panel is not tripped.

Call (647) 657-2977 Book a service call

Licensed technicians serving Vaughan, Toronto and the GTA.

What does Rheem error code 30 mean?

The 24 V fuse on the furnace control has blown, usually because a low-voltage wire is shorted to common or ground. Nothing else runs while this code is up.

Applies to: (-)96VA040-115 (R96V / U96V) and (-)(-)96MDV040-115 two-stage variable-speed communicating furnaces

Common causes of Rheem code 30

24 VAC short to ground or common on the thermostat / low-voltage wiring
Pinched thermostat cable
Miswired accessory or condenser

Safety: Gas, electrical and refrigerant work must be done by a licensed technician. Turn off power and gas before servicing, never bypass a safety control, and always follow the manufacturer's manual for your exact model.

Rheem models that use code 30

96MDV040B30A 96MDV060B30A 96MDV070B30A 96MDV085C50A 96MDV100C50A 96MDV115D50A R96VA0401317MSA R96VA0601317MSA R96VA0701317MSA R96VA0851521MSA R96VA1001521MSA R96VA1151524MSA

Other Rheem Furnace codes

Code	Meaning
13	Flame lost
14	Unexpected flame
20	Twinning fault
22	Main limit open
23	HALC limit open (HALC LIMIT OPEN)
26	Line and neutral reversed
33	Rollout switch (MRLC) open
44	Low pressure switch closed (stuck)
45	Low pressure switch open - inducer high speed
46	Low pressure switch open - inducer low speed
55	Pressure switch stuck closed
57	Pressure switch stuck open

All Rheem Furnace error codes →

Rheem code 30: homeowner questions

What does Rheem code 30 mean?

Open fuse. The 24 V fuse on the furnace control has blown, usually because a low-voltage wire is shorted to common or ground. Nothing else runs while this code is up.

Is it safe to keep using my furnace with code 30?

No. Code 30 is a safety shutdown, so keep the furnace off until a licensed technician has checked it.

Can I reset Rheem code 30 myself?

Do not keep resetting it. Repeated resets can hide a safety problem; a licensed technician needs to find the cause.

Who can fix Rheem code 30 near me?

Aurora Star Tech Inc. repairs Rheem furnaces in Vaughan, Toronto and across the GTA. Call (647) 657-2977 or book a service call online.

Homeowner help: Furnace Not Turning On: What to Check · Furnace Blinking Light: What the Flash Codes Mean

Troubleshooting guides

Blowing cold air All brands · Furnace
No heat All brands · Furnace
Short cycling All brands · Furnace
Blower codes 66, 61 and 60 - what to look for Rheem · Furnace
Blower does not start after burners light Rheem · Furnace
Burners go out before the heat call ends / short cycling Rheem · Furnace
Clear the fault history Rheem · Furnace
Clearing lockouts Rheem · Furnace
Codes look upside down - display orientation switch S1-1 Rheem · Furnace
Communicating system not found / no communication Rheem · Furnace
ECM blower does not start on heat Rheem · Furnace
ECM blower will not run - power and communication checks (code 68) Rheem · Furnace
Extended display mode Rheem · Furnace
Force low or high fire for testing (RGPE/RGLE) Rheem · Furnace
Furnace no heat - sequence troubleshooting Rheem · Furnace
Furnace short cycles or does not hold setpoint Rheem · Furnace
Gas valve does not shut off when heat call ends Rheem · Furnace
Heat call troubleshooting walk-through (two-stage communicating IFC) Rheem · Furnace
Indoor blower does not start after burners light Rheem · Furnace
Inducer (draft motor) does not start on heat call Rheem · Furnace
Inducer does not run / does not run on low speed Rheem · Furnace
Inducer runs 60 s then shuts off for 5 minutes, or runs continuously Rheem · Furnace
Inducer runs 60 seconds then off for 5 minutes Rheem · Furnace
No heat - inducer (IDM) does not start Rheem · Furnace
No heat - POWER LED off Rheem · Furnace
Pushbutton status menu: fault history, CFM, fire rate, unit size, temperature rise Rheem · Furnace
Read or clear the six-fault history from the thermostat (RGPE/RGLE) Rheem · Furnace
Read target airflow from the CFM LED Rheem · Furnace
Replacing the furnace control: keep the memory card and copy the dipswitches Rheem · Furnace
Replay or clear the fault history on power-up (802P / 80MDP / R95P) Rheem · Furnace
Replay or clear the last five faults (RGPE/RGLE) Rheem · Furnace
Reset a soft lockout (R95P) Rheem · Furnace
Single-stage thermostat on a two-stage furnace: auto staging Rheem · Furnace
Test communication with the LEARN button (RGPE/RGLE) Rheem · Furnace
Thermostat does not hold room temperature Rheem · Furnace

Source: Rheem (-)96V / (-)(-)96MDV Installation Instructions 92-24161-124-08, Table 20 p.116. Written in our own words as a summary; always check the original manual.

General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.