Model # 460353
Designed specifically for aboveground pools
The MINIMAX 100 is a compact, low-profile heater that's big on efficiency, performance, and convenience. With an input of 100,000 BTUs, the MINIMAX 100 is the perfect size for heating even the largest aboveground pool.
The MINIMAX 100 is designed for fast heat-up, low operating costs, and long life. It's available in reliable direct-spark ignition and millivolt versions for propane or natural gas. And best of all, it costs surprisingly little to operate.
Additional features include:
Energy-efficient design for minimal fuel consumption and low operating cost.
Quiet and dependable operation from proven packaged burner system.
Stainless steel burners for long, corrosion-free life.
Ceramic tile insulation prevents heat loss for greater heat transfer efficiency and cool-to-the-touch exterior.
Low-profile design with rounded corners is visually attractive
User-friendly controls make operation simple and trouble-free.
Prewired for automatic pool/spa controls.
Built-in vent top for efficient combustion.
Bronze headers for durability.
Flow valve senses both water temperature and pressure for optimal flow.
1 1/2" NPT connections for easy installation.
How long will a 20 lb propane tank last with a 100,000 btu heater?
On average, it takes 1 gallon of propane per hour per 100,000 btu's. A 20 lb tank would not last that long. Aside from the size, you will want to check with your local code regarding propane tank restrictions.
I have a small (5400 gal) in ground pool, indoors so no heat from the sun. I believe this size heater will do the trick but every website says it is for above ground pools. Does that matter, or do they say that because of the typical sizes of above ground vs in ground? Heater will be outside, so no need for a stack and I only use it spring through fall so I am not concerned with having extra BTUs for winter heat.
We double checked Pentair's documentation on this heater and yes this heater may be used on small inground pools. The documentation states the following "...for use on aboveground pools, spas or small inground pools...." For your situation I believe this heater would be a good fit for you.