The best propane-fueled water heaters on the market as of 2015 are produced by Rinnai, according to review sites ToastyReviews and BestReviews. The Rinnai RL94eP and RL75iN tankless water heater models were specifically cited as excellent.
The Rinnai RL94eP water heater is a native propane-fueled water heater capable of delivering up to 9.4 gallons of heated water per minute, making it ideal for larger homes. The RL7iN is a natural gas model but can be converted to use propane. It produces 7.5 gallons of heated water per minute. For consumers who require an outdoor water heater, the propane-fueled V65EP model from Rinnai is also considered tops in its class.