
100109902 Comparison
| photo | price | summary | rating |
|---|---|---|---|
![]() | $49.00 | Condition is Open box, 100109877 A.O. Smith 9004513215 Pressure Switch-HI Gas 020363136901, shipping cost = $8.00 | 99.9% |
| photo | price | summary | rating |
|---|---|---|---|
![]() | $50.00 | Condition is New, A.O. Smith 9004513215 PRESSURE SWITCH-HI GAS, shipping cost = $6.00 | 100.0% |
| photo | price | summary | rating |
|---|---|---|---|
![]() | $40.00 | Condition is New – Open box, SCHNEIDER ELECTRIC 17426 277V 15A NSMP, shipping cost = $16.50 | 99.9% |

Smith 100109902 Lochinvar AO Water Heater High Pressure Switch
The Smith 100109902 high pressure switch is a crucial component of the Lochinvar AO series water heaters. This switch is designed to ensure the safe and efficient operation of your water heater by monitoring the incoming water pressure and activating safety measures when necessary.
This high pressure switch is a precision-engineered device, featuring a robust and corrosion-resistant design. It is constructed from high-quality materials, including brass terminals and a thermoplastic housing, which not only provide durability but also help to prevent leaks and other potential issues.
The Smith 100109902 high pressure switch is designed to operate in high-pressure environments, making it an ideal choice for commercial and industrial water heating applications. It is rated for a maximum working pressure of 150 psi (pounds per square inch) and a temperature range of 32 F to 185 F (0 C to 85 C).
One of the key features of this high pressure switch is its ability to automatically reset after a safety trip. This means that once the pressure or temperature issue has been resolved, the switch will reset and allow the water heater to continue operating. However, if the issue persists, the switch will continue to trip, alerting you to the need for further investigation and maintenance.
Installation of the Smith 100109902 high pressure switch is straightforward, with clear instructions provided in the user manual. The switch is easily accessible, located on the side of the water heater, and can be replaced quickly and easily when necessary.
In summary, the Smith 100109902 high pressure switch is an essential component of the Lochinvar AO series water heaters. Its robust design, high pressure rating, and automatic reset feature make it an ideal choice for commercial and industrial water heating applications. With its ease of installation and replacement, this switch provides peace of mind and ensures the safe and efficient operation of your water heater.
Buying a high pressure switch for a water heater, such as the Smith 100109902 Lochinvar AO model, can have both advantages and disadvantages. Here are some potential pros and cons to consider:
Pros:1. Safety: A high pressure switch helps ensure the safe operation of your water heater by shutting off the water supply if the pressure exceeds a certain level. This can prevent damage to the heater or potential safety hazards.
2. Compliance: Depending on local regulations, a high pressure switch may be required for water heaters, particularly in commercial or industrial applications.
3. Easy installation: The Smith 100109902 high pressure switch is designed for easy installation, with a simple wiring harness and clear instructions.
4. Durability: Lochinvar is known for manufacturing high-quality products, and the Smith high pressure switch is no exception. It is built to withstand high temperatures and pressures, ensuring long-lasting performance.
Cons:1. Cost: Replacing a high pressure switch can be an additional expense for water heater owners. While not extremely costly, it is an added cost that may not be necessary for all applications.
2. Complexity: While the installation process is straightforward, understanding the underlying pressure and safety requirements for a water heater can be complex. Hiring a professional to install or diagnose the issue may be necessary.
3. Limited lifespan: High pressure switches, like any mechanical component, have a finite lifespan. Regular maintenance and inspections are necessary to ensure the switch is functioning properly and to extend its lifespan.
Conclusion:The decision to purchase a high pressure switch for a water heater, such as the Smith 100109902 Lochinvar AO model, ultimately depends on the specific application and local regulations. The advantages, such as safety and compliance, may outweigh the disadvantages for some users. However, the added cost and potential complexity may deter others. If safety and regulatory compliance are concerns, or if the water heater is in a high-pressure application, then the investment in a high pressure switch is likely worthwhile. For other applications, regular maintenance and inspections may be sufficient to ensure the safe and efficient operation of the water heater.
Recommendation:If you are unsure about the need for a high pressure switch for your water heater, consult with a professional plumber or the local building codes to determine the requirements for your specific application. If a high pressure switch is necessary, consider the Smith 100109902 Lochinvar AO model for its ease of installation, durability, and safety features.
Details:
New - ao Smith water heater 100109902 high pressure switch.
specifications indusswitch:
- brand: A. O. Smith
- mpn: 100109902
- model: 9004513215
- part type: Water Pressure Heater Switch Gauge
- fuse type: Switch
shipping indusswitch:
- class: standard
- service: usps ground advantage
- type: calculated
- carrier: usps
- transit: 4-10 days
offer indusswitch:
- availability: in stock
- started: december 9, 2025
- prices: $49.00–$50.00
- item condition:
- Open box
- New
- New – Open box
- options: ship-to-home
- in stock #: 3
- sold #: 13
- best offers: true
returns indusswitch:
- policy: no returns
payments indusswitch:
- other
- wallet: paypal
- credit card: discover
general indusswitch:
- category: Business & Industrial > Electrical Equipment Supplies > Pressure Switches
seller indusswitch:
- rating: 99.9%
- # reviews: 8067
- city: wagoner, oklahoma
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