Pentair MasterTemp® Natural Gas Heater 400K BTU
The Pentair MasterTemp® Natural Gas Heater 400K BTU offers all the efficiency, convenience, and reliability features you want in a pool heater — plus a lot more. As easy to use as your home heating system, with a user-friendly LCD display and troubleshoot icons that make system operation and monitoring a snap. The compact design and super-quiet operation won't intrude on your poolside leisure time.
Built by Pentair with an HD copper heat exchanger rated for low pH, high flow, and heavy use applications. 400,000 BTU natural gas for larger pools and spas. Backed by a 1-year parts warranty.
⚠️ Professional Installation Required. Pool heater installation involves gas line connections and electrical wiring. Always use a licensed contractor to ensure safety, code compliance, and warranty validity.
Key Features
400,000 BTU Natural Gas
Maximum-capacity heating for larger pools and spas.
HD Copper Heat Exchanger
Heavy-duty copper exchanger rated for low pH, high flow, and heavy use applications.
LCD Display with Troubleshoot Icons
User-friendly LCD display makes system operation and monitoring a snap.
Compact, Quiet Design
Super-quiet operation — won't intrude on poolside leisure.
Indoor and Outdoor Rated
Suitable for both indoor and outdoor pool and spa installations.
1-Year Parts Warranty
Pentair parts warranty coverage.
Who It's For
- Larger pool and spa owners wanting a 400K BTU MasterTemp with LCD display controls
- Applications with low pH, high flow, or heavy use suited to an HD copper heat exchanger
- Indoor and outdoor installations at maximum BTU capacity
Specifications
Heating Performance
| BTU Input | 400,000 BTU |
| Fuel Type | Natural Gas |
Construction
| Heat Exchanger | Copper (HD) |
| Control Type | LCD Display with Troubleshoot Icons |
Installation
| Application | Indoor / Outdoor / Pool / Spa |
| Frequency | 60 Hz |
Physical
| Product Weight | 159 lb |
| Cabinet Dimensions | 27 W × 35 D × 36 H in |
| Shipping Dimensions | 36 × 22.5 × 30 in |
Approvals & Warranty
| Warranty | 1 Year Parts |
What's in the Box
- Pentair MasterTemp 400K BTU Natural Gas Heater
- Union Fittings
- User Manual
Warranty
The MasterTemp 400K NG (EC-462028) comes with a 1-year parts manufacturer warranty from Pentair. Clearflow Pool Supply is an authorized Pentair dealer and will assist with any warranty service needed.
Downloads
Frequently Asked Questions
How does this compare to the other MasterTemp 400K NG models?
The EC-462028 uses a copper (not cupro nickel) HD heat exchanger, an LCD display with troubleshoot icons, and carries a 1-year parts warranty. The standard 460736 uses the same LCD display with a 2-year warranty and cupro nickel tubing. The 460805 HD and 461021 ASME HD models feature cupro nickel tubing with 2-year warranties. For salt water or chemically aggressive pools, the cupro nickel tubing models are generally preferred over copper.
Does this heater require professional installation?
Yes. Gas heater installation involves connecting to a natural gas supply line, electrical wiring, and proper venting. A licensed pool contractor or plumber must perform the installation to ensure safety, local code compliance, and warranty validity.
What size pool is the 400K BTU suitable for?
As a general guideline, 400,000 BTU is typically suited for pools in the 30,000–50,000 gallon range depending on climate, desired temperature rise, and heat loss factors. A licensed pool professional can calculate the correct BTU requirement for your specific pool and location.
Can it be used indoors?
Yes. The MasterTemp is rated for both indoor and outdoor installation. Indoor installations require proper venting per local code. Consult the install guide and a licensed contractor for indoor venting requirements.