Raypak AVIA 404A
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 $4,420.27$4,420.27
3.9/5
A strong pick for in-ground pools already on Pentair automation, though online buyers get only a short warranty.
- 400,000 BTU/hHeating input
- 84%Efficiency
- Natural gas or propaneGas type
- 1 yearWarranty
Check price at Amazon$4,079
Price checked October 31, 2026. As an Amazon Associate we earn from qualifying purchases.
Pros
- Plugs straight into Pentair automation over RS-485 for scheduling and app control
- Low NOx and certified for indoor or outdoor installs
- Copper heat exchanger reaches 84% efficiency, among the best for a non condensing heater
- Light cabinet for its size is easier to place and service
Cons
- Only a 1 year parts warranty when bought online
- Plain copper heat exchanger is less forgiving of salt and low pH than cupro-nickel
- Needs a large gas supply line
The Pentair MasterTemp family
Every Pentair MasterTemp model we rank, smallest first. Ratings compare each against its own size.
| Model | Heating input | Rating | Price |
|---|---|---|---|
| Pentair MasterTemp 125 | 125,000 BTU/h | 2.6/5 | $2,098 |
| Pentair MasterTemp 250 | 250,000 BTU/h | 2.7/5 | $3,098 |
| Pentair MasterTemp 400 (this one) | 400,000 BTU/h | 3.9/5 | $4,079 |
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
| Heating | |
|---|---|
| Gas input | 400,000 BTU/h |
| Gas type | Natural gas or propane |
| Thermal efficiency | 84% |
| Condensing | No |
| Low NOx | Yes |
| Heat exchanger | Copper |
| Max water flow | 120 GPM |
| Installation and controls | |
| Ignition | Electronic |
| Venting | Both |
| Digital controls | Yes |
| Automation or app | Yes |
| Weight | 136 lb |
| Warranty | 1 year |
Alternatives in this size
Raypak AVIA HD NiTek 404A
For salt pool owners who want the AVIA features with a tougher heat exchanger and will pay extra for it.
Amazon $4,923$4,923
Raypak Digital 406A
Good value for in-ground pools outside low NOx areas, provided it comes from an authorized dealer so the warranty holds.
Amazon $4,421.17$4,421.17
Compare
Compare the Pentair MasterTemp 400 with any other gas pool heater →
More from Pentair: every Pentair product ranked.