Products and configurations to compare
Mopeka Pro Check sensor
Current recreational sensor supports common 20/30/40-lb DOT cylinders with spacers.
Best when: you want phone-based LPG level on standard steel RV cylinders
Watch for: sensor does not work on every tank material and requires clean bottom contact
Mopeka dual-sensor kit/display
Useful on automatic-changeover two-cylinder systems.
Best when: you want both RV cylinders visible without opening the compartment
Watch for: higher cost and more sensors/batteries
Mopeka tank spacers / replacement battery
Spacing protects the under-tank sensor from being crushed.
Best when: bottom clearance or battery replacement is needed
Watch for: use the correct sensor accessories
Ultrasonic measurement is different from pressure gauges
It senses the liquid interface through the tank wall rather than interpreting vapor pressure.
Bottom contact must be clean
Rust, debris or poor coupling can affect readings.
Cylinder material matters
The current cited Pro sensor notes limitations and model/region differences; verify your tank type.
Bluetooth range depends on the RV
Metal compartments can reduce signal; optional displays/bridges can change the workflow.
Do not confuse level with safety
A full/empty reading says nothing about leaks or regulator condition.
Tank level and leak safety are different problems
An ultrasonic tank sensor estimates how much liquid propane remains. It is not a gas-leak detector, regulator monitor or emergency shutoff. A mechanical pressure-style gauge has limitations because propane pressure stays relatively stable through much of the usable fill; weight or ultrasonic liquid-level measurement gives a more direct picture of remaining fuel.
Any suspected propane leak, regulator issue or abnormal odor is a safety issue, not a shopping comparison. Shut off fuel when appropriate, ventilate, avoid ignition sources and follow RV/LP-system professional guidance.
Remote level data is most valuable before the cold night
For furnace-heavy camping, knowing a cylinder is low before bedtime is the real value. Bluetooth and display bridges are convenience layers; they do not change the underlying tank capacity or regulator behavior.
Before checkout
- Exact RV voltage, amp service and existing component model are known
- Physical dimensions and service access are measured
- Wire, hose, port and fitting sizes are confirmed before ordering
- Product duty cycle/output matches the real worst-case load
- Cold-weather requirements are considered
- Consumables and replacement parts remain available
- Installation does not defeat factory protection or ventilation
- Mobile-app features are not required for basic emergency operation
- Return policy allows a real fit/compatibility check
- Professional installation cost is included where appropriate
Fitment and installed cost matter more than the sale price
RV equipment rarely exists in isolation. A cheaper pump that needs new fittings, a lithium battery that forces a converter change, a soft start that needs professional rooftop labor or an inverter that requires new cable/fusing can cost more installed than the premium part that actually matches the rig. Write down the entire install list before comparing prices.
Also measure service access. Components eventually need filters cleaned, bolts checked, firmware/app access, batteries changed or hoses disconnected. An installation that technically fits but cannot be serviced without dismantling a cabinet is not a good installation.
First-trip test
Test new systems close to home before depending on them several states away. Inflate every RV tire, run the pump through several faucets, cycle the AC repeatedly on the intended generator, dump through the sanitation setup, or run the inverter under realistic loads. Watch for heat, voltage drop, leaks, vibration, nuisance alarms and connection loosening. Fix those problems before the long trip.
Keep the old functional component when practical until the replacement survives that shakedown. A known-working pump, charger or level can be valuable backup while a new installation is still proving itself.
Frequently asked questions
Does Mopeka Pro Check work on 20-lb tanks?
Current North American Pro Check documentation includes common 20/30/40-lb DOT cylinders with spacers.
What battery does it use?
A replaceable CR2032.
Does it detect propane leaks?
No. It is a liquid-level sensor.
Can I read it without a phone?
Mopeka sells compatible display/bridge options; verify current accessory compatibility.
Current manufacturer/source checks
Affiliate disclosure: RVGear.co is reader-supported. Amazon links use Associates tag scouttheory-20 and eBay links use Partner Network campaign 5339137014. We may earn a commission at no extra cost to you.