Sta-Rite Max-E-Therm 400
A Pentair built heater for owners on Pentair automation who want low NOx and high efficiency; compare prices with the MasterTemp first.
Amazon $4,499$4,499
3.5/5
Good value for in-ground pools outside low NOx areas, provided it comes from an authorized dealer so the warranty holds.
- 332,000 BTU/hHeating input
- 82%Efficiency
- Natural gas or propaneGas type
- 2 yearsWarranty
Check price at Amazon$3,615
Price checked October 31, 2026. As an Amazon Associate we earn from qualifying purchases.
Pros
- Two years of parts and labor coverage beats the one year online warranty of most rivals
- Lowest price per BTU among the big name heaters
- Indoor or outdoor installation fits more equipment pads
- Large input heats an in-ground pool quickly
Cons
- Not low NOx, so it cannot be sold or installed in California and other strict air districts
- Warranty is void if the seller is not an authorized Raypak dealer, so check the seller first
- Plain copper heat exchanger is less tolerant of salt and low pH
The Raypak Digital family
Every Raypak Digital model we rank, smallest first. Ratings compare each against its own size.
| Model | Heating input | Rating | Price |
|---|---|---|---|
| Raypak Digital 206A | 199,000 BTU/h | 3.8/5 | $3,023 |
| Raypak Digital 266A | 266,000 BTU/h | 2.9/5 | $3,249 |
| Raypak Digital 336A (this one) | 332,000 BTU/h | 3.5/5 | $3,615 |
| Raypak Digital 406A | 399,000 BTU/h | 3.9/5 | $4,421.17 |
How it scores
The rating comes from 4 measured or published factors, each scored 0-100 against fixed reference points for its size. How we rank explains each one.
Specifications
| Model number | P-R336A-EN-C / P-R336A-EP-C |
|---|---|
| Heating | |
| Gas input | 332,000 BTU/h |
| Gas type | Natural gas or propane |
| Thermal efficiency | 82% |
| Condensing | No |
| Low NOx | No |
| Heat exchanger | Copper |
| Max water flow | 100 GPM |
| Installation and controls | |
| Ignition | Electronic |
| Venting | Both |
| Digital controls | Yes |
| Automation or app | Yes |
| Warranty | 2 years |
Alternatives in this size
Hayward H-Series H400FD
A low NOx, salt tolerant in-ground pool heater for owners who buy online and can live with a short warranty.
Amazon $5,099$5,099
Raypak AVIA 264A
The best rounded in-ground pool heater here for most owners: efficient, low NOx and app controlled with a longer warranty, if bought from an authorized dealer.
Amazon $3,489.52$3,489.52
Compare
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