Which heater is better for a 20,000-gallon pool?

The Raypak. Its 266,000 BTU output is sized for pools up to about 25,000 gallons, while the Pentair's 125,000 BTU is rated for up to 15,000 gallons.

Is the Raypak worth the extra $1,513?

Only if you have natural gas and a pool larger than about 15,000 gallons. For a small propane-heated pool, the Pentair does the job for far less.

Can I use the Pentair with natural gas?

The 461061 is the propane model. Pentair sells separate natural gas versions of the MasterTemp, so check the part number before ordering.

Which one lasts longer?

The Raypak has an edge on paper. Its Protek Shield targets heat exchanger corrosion, the usual cause of failure, and it carries an extended two-year warranty.

Do both work with pool automation?

The Pentair connects to IntelliCenter, EasyTouch and IntelliTouch. The Raypak uses its own digital control panel and has no Pentair automation link.

Which needs more plumbing capacity?

The Raypak accepts up to 125 gal/min versus 70 gal/min for the Pentair, so it pairs better with high-flow variable-speed pump setups.

Pentair MasterTemp 125K BTU Pool Heater vs Raypak 266,000 BTU Digital Gas Pool Heater

Buy the Pentair MasterTemp 461061 if you have a propane tank and a pool up to about 15,000 gallons. Buy the Raypak 266,000 BTU if you have a natural gas line and a pool up to about 25,000 gallons, and you want roughly double the heat output. The Pentair is far cheaper: $1,736.12 at Pool Supply Harbor versus $3,249.00 at Pool Cleaning Parts, both as of November 7, 2026. The Raypak costs about $1,513 more, but it heats a much larger pool and runs on natural gas.

Today the Pentair MasterTemp 125K BTU Pool Heater costs $1,512.88 less at its best price.

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