Mr. Heater Big Buddy Back Cover Fan E78404 — Do You Really Need It in 2026?
The E78404 adds a fan to your Mr. Heater Big Buddy MH18B propane heater. It only makes sense as an upgrade if you already own that specific heater.
Check Price on AmazonAs an Amazon Associate we earn from qualifying purchases.
Key Specifications
Best For
How this product scores for different use cases
Our Verdict
This is not a space heater. It is a fan attachment that clips onto the back of the Mr. Heater Big Buddy MH18B propane heater.
The fan adds active airflow to the Big Buddy. It pushes warm air further into your space instead of letting it rise passively.
Garages and outdoor areas are the best fit. That is where the Big Buddy already performs well and where this fan makes the most difference.
This accessory has no safety features of its own. No tip-over protection. No overheat shutoff. No thermostat control.
Only buy this if you already own the Big Buddy MH18B. For everyone else, it delivers no heating value on its own.
What We Like
- The integrated fan has its own on/off switch. You control airflow without adjusting the heater itself.
- Made by Mr. Heater, the leading brand in portable propane heating products.
- Fits the MH18B Big Buddy without any tools or modification.
- Adds active heat circulation to a heater that distributes heat passively by default.
- Built and rated for outdoor use. It handles cold and rugged conditions.
What Could Be Better
- No wattage or BTU output of its own. You cannot evaluate its heating contribution independently.
- No tip-over protection. Most standalone space heaters include this as a basic safety feature.
- No overheat shutoff. Competing standalone heaters include automatic overheat protection as standard.
- No thermostat. You cannot set or hold a target temperature with this unit.
- At $64.40, this fan cover costs more than some entry-level standalone electric space heaters.
Standout Features
Full Specifications
Additional Info
| Assembly | No |
Frequently Asked Questions
Common questions about Mr. Heater Big Buddy Heater Back Cover Fan, E78404
Does this fan work without a Mr. Heater Big Buddy heater?
No. The E78404 is an accessory that attaches to the Mr. Heater Big Buddy MH18B. It does not produce heat or operate on its own.
Can I use this indoors?
No. The product is rated for outdoor use only. Using it indoors falls outside its listed application.
What powers the fan?
The fan draws power from the Big Buddy heater it attaches to. You do not need a separate battery or power cord.
Does the E78404 have tip-over protection or overheat shutoff?
No. This accessory has no listed safety features of its own. Safety systems are built into the MH18B heater it connects to.
How does this attach to the Big Buddy heater?
It replaces the standard back cover of the Mr. Heater Big Buddy MH18B. No modification to the heater is needed for installation.
Best For
How this product scores for different use cases
Scores
Free shipping on eligible orders
See Today's PriceTags
More from Mr. Heater
See All →
Other Heaters You Might Like
Browse All →
Wall Space Heater 350W Portable Electric Heater with Programmable Adjustable Thermostat, Overheat Protection
Space Heaters Indoor Use, 26" 12ft/s Electric Heater with Remote, 1500W Electric Heaters with 75°Oscillation, 1-12H Timer, PTC Electric Heater for Large Room, Bedroom Home Office, 2024 Upgraded
Abolee Space Heater, Electric Heater with Thermostat, 18 Inch Portable Heater with 70°Oscillation, 12H Timer, Overheating & Tip-Over Protection, Fast Safety Heat for Home, Bedroom HP1502, Black
Abolee Space Heaters with Motion Sensor, 1500W Ceramic Heating with Remote, Portable Electric Heaters for Indoor Use with Thermostat, 70° Oscillating, Digital Thermostat, for Bedroom Home Office
Ready to buy the Mr. Heater E78404?
Free shipping available on eligible orders.
See Today's Price on Amazon