A heater under 250,000 BTU/h suits an above-ground pool, a spa, or a small in-ground pool up to about 15,000 gallons. It needs a smaller gas line than the big units, which can save real money on installation, especially on propane.
Prices were last checked October 31, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Full ranking 8
- Raypak Digital 206A#1 of 8Full review
Good value for spas and small pools outside low NOx areas, provided it comes from an authorized dealer so the warranty holds.
Amazon $3,023$3,023199,000 BTU/h82%2 years - Sta-Rite Max-E-Therm 200#2 of 8Full review
A Pentair built heater for owners on Pentair automation who want low NOx and high efficiency; compare prices with the MasterTemp first.
Amazon $3,650$3,650200,000 BTU/h84%1 year - Raypak 156A#3 of 8Full review
A low cost heater for above-ground pools and spas outside low NOx areas.
Amazon $2,290.44$2,290.44150,000 BTU/h82%2 years - Hayward H-Series H200FD#4 of 8Full review
A low NOx, salt tolerant spa or small pool heater for owners who buy online and can live with a short warranty.
Amazon $3,699$3,699199,900 BTU/h83%1 year - Pentair MasterTemp 125#5 of 8Full review
A compact, light heater for spas and above-ground pools, best for owners with Pentair automation.
Amazon $2,098$2,098125,000 BTU/h82%1 year - Hayward H-Series H150FD#6 of 8Full review
A low NOx, salt tolerant spa or small pool heater for owners who buy online and can live with a short warranty.
Amazon $2,999$2,999150,000 BTU/h82.7%1 year - Hayward H-Series H135FD#7 of 8Full review
An affordable heater for above-ground pools and spas where a short warranty and outdoor only installation are acceptable.
Amazon $2,399$2,399135,000 BTU/h82%1 year - Raypak 106A#8 of 8Full review
A low cost heater for above-ground pools and spas outside low NOx areas.
Amazon $2,119$2,119105,000 BTU/h82%2 years
