Dometic Atwood Furnace High Temperature Limit Switch - Fits 8500, 8900, 7900 Series - Part# 37021
Dometic Atwood Furnace High Temperature Limit Switch - Fits 8500, 8900, 7900 Series - Part# 37021
The Dometic Atwood High Temperature Limit Switch (Part# 37021) is a critical safety component that protects your RV furnace from overheating. This switch automatically shuts off the furnace if internal temperatures exceed safe operating limits, preventing damage to the heating system and ensuring safe operation. If your Atwood furnace is cycling on and off unexpectedly or won't stay lit, a faulty limit switch is often the culprit.
Key Features
- Critical Safety Component: Automatically shuts off furnace operation when temperatures exceed safe limits
- Genuine Dometic OEM Part: Factory replacement part engineered specifically for Atwood furnaces
- Direct Replacement: Exact fit for original equipment - no modifications required
- Prevents Furnace Damage: Protects heating elements and internal components from heat-related failure
- Easy Diagnosis: Common failure point when furnace won't stay running or cycles erratically
- Durable Construction: Built to withstand repeated thermal cycling in demanding RV environments
Technical Specifications
| Part Number | 37021 |
| Component Type | High Temperature Limit Switch |
| Application | Atwood RV Furnaces |
| Function | Overheat Protection / Safety Shutoff |
| Replacement Type | Direct OEM Replacement |
Compatible Furnace Models
| Furnace Series | Common Applications |
| Atwood 8500 Series | 8500-II, 8500-III, 8500-IV |
| Atwood 8900 Series | 8900-II, 8900-III, 8900-IV |
| Atwood 7900 Series | 7900-II, 7900-III |
| Verify your furnace model number before ordering to ensure proper fit | |
Frequently Asked Questions
How do I know if my limit switch has failed?
Common symptoms include the furnace starting but shutting off after a few seconds, repeated cycling without heating, or the furnace not igniting at all. If the furnace runs briefly then stops, the limit switch may be tripping due to actual overheating or switch failure. Always check for blocked vents and proper airflow before replacing the switch.
Can I test the limit switch before replacing it?
Yes, with the furnace off and cooled down, you can use a multimeter to test for continuity across the switch terminals. A functioning switch should show continuity when cool. If there's no continuity at room temperature, the switch has failed in the open position and needs replacement. Always disconnect power before testing.
Is this switch difficult to replace?
Most RV owners with basic mechanical skills can replace this switch. It typically involves removing the furnace cover, disconnecting two wire terminals, removing mounting screws, and reversing the process with the new switch. Always turn off power at the breaker and allow the furnace to cool completely before beginning work. Consult your furnace service manual for specific instructions.
Why does my limit switch keep failing?
Repeated limit switch failures usually indicate an underlying problem causing actual overheating. Check for restricted airflow due to dirty filters, blocked intake or exhaust vents, failed blower motor, or debris inside the furnace chamber. Address these issues to prevent premature failure of the replacement switch.
Why Choose Elkhart RV Parts?
At ElkhartRVParts.com, we specialize in hard-to-find Dometic and Atwood furnace parts that keep your RV heating system running safely and efficiently. Located in Elkhart, Indiana — the RV Capital of the World — we understand the importance of reliable furnace operation, especially during cold-weather camping. We stock genuine OEM replacement parts and ship fast so you can get back to comfortable RVing.
Our team knows Atwood furnaces inside and out. Whether you're troubleshooting a heating issue or performing preventive maintenance, we're here to help you find the exact part you need. Every component we sell meets or exceeds original equipment specifications for reliable, long-lasting performance.
✓ Genuine Dometic OEM Parts
✓ Fast Shipping from Elkhart, Indiana
✓ Expert RV Parts Support
Original: $36.89
-65%$36.89
$12.91Product Information
Product Information
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Description
The Dometic Atwood High Temperature Limit Switch (Part# 37021) is a critical safety component that protects your RV furnace from overheating. This switch automatically shuts off the furnace if internal temperatures exceed safe operating limits, preventing damage to the heating system and ensuring safe operation. If your Atwood furnace is cycling on and off unexpectedly or won't stay lit, a faulty limit switch is often the culprit.
Key Features
- Critical Safety Component: Automatically shuts off furnace operation when temperatures exceed safe limits
- Genuine Dometic OEM Part: Factory replacement part engineered specifically for Atwood furnaces
- Direct Replacement: Exact fit for original equipment - no modifications required
- Prevents Furnace Damage: Protects heating elements and internal components from heat-related failure
- Easy Diagnosis: Common failure point when furnace won't stay running or cycles erratically
- Durable Construction: Built to withstand repeated thermal cycling in demanding RV environments
Technical Specifications
| Part Number | 37021 |
| Component Type | High Temperature Limit Switch |
| Application | Atwood RV Furnaces |
| Function | Overheat Protection / Safety Shutoff |
| Replacement Type | Direct OEM Replacement |
Compatible Furnace Models
| Furnace Series | Common Applications |
| Atwood 8500 Series | 8500-II, 8500-III, 8500-IV |
| Atwood 8900 Series | 8900-II, 8900-III, 8900-IV |
| Atwood 7900 Series | 7900-II, 7900-III |
| Verify your furnace model number before ordering to ensure proper fit | |
Frequently Asked Questions
How do I know if my limit switch has failed?
Common symptoms include the furnace starting but shutting off after a few seconds, repeated cycling without heating, or the furnace not igniting at all. If the furnace runs briefly then stops, the limit switch may be tripping due to actual overheating or switch failure. Always check for blocked vents and proper airflow before replacing the switch.
Can I test the limit switch before replacing it?
Yes, with the furnace off and cooled down, you can use a multimeter to test for continuity across the switch terminals. A functioning switch should show continuity when cool. If there's no continuity at room temperature, the switch has failed in the open position and needs replacement. Always disconnect power before testing.
Is this switch difficult to replace?
Most RV owners with basic mechanical skills can replace this switch. It typically involves removing the furnace cover, disconnecting two wire terminals, removing mounting screws, and reversing the process with the new switch. Always turn off power at the breaker and allow the furnace to cool completely before beginning work. Consult your furnace service manual for specific instructions.
Why does my limit switch keep failing?
Repeated limit switch failures usually indicate an underlying problem causing actual overheating. Check for restricted airflow due to dirty filters, blocked intake or exhaust vents, failed blower motor, or debris inside the furnace chamber. Address these issues to prevent premature failure of the replacement switch.
Why Choose Elkhart RV Parts?
At ElkhartRVParts.com, we specialize in hard-to-find Dometic and Atwood furnace parts that keep your RV heating system running safely and efficiently. Located in Elkhart, Indiana — the RV Capital of the World — we understand the importance of reliable furnace operation, especially during cold-weather camping. We stock genuine OEM replacement parts and ship fast so you can get back to comfortable RVing.
Our team knows Atwood furnaces inside and out. Whether you're troubleshooting a heating issue or performing preventive maintenance, we're here to help you find the exact part you need. Every component we sell meets or exceeds original equipment specifications for reliable, long-lasting performance.
✓ Genuine Dometic OEM Parts
✓ Fast Shipping from Elkhart, Indiana
✓ Expert RV Parts Support
