Product Overview

The Pentair MasterTemp® HD 400 K BTU Heater (model 460805) is a high-performance natural gas heater designed for large residential in-ground pools and demanding applications. Featuring a heavy-duty cupro-nickel heat exchanger, digital diagnostics, and low NOx emissions certification, this unit delivers robust heating capacity and long-term durability for challenging environments.

Ideal For

• Pool owners with large volume pools (or spa + pool combinations) in need of a powerful 400,000 BTU heater.

• Installations where durability is critical—such as salt water pools, elevated flow rates, or heavy usage.

• Service professionals specifying a premium heater that provides high performance, digital controls and OEM reliability.

• Upgrades from older or under-sized heaters where both run-time and recovery time need to be improved.

Key Features

• 400,000 BTU Output – Class-leading heating capacity suitable for large pool/spa systems.

• Heavy-Duty Cupro-Nickel Heat Exchanger – engineered for harsh water conditions, corrosion resistance and long service life.

• Digital Display & Diagnostics – user-friendly interface allowing set-point selection and system fault monitoring.

• Low NOx Emissions Certified – meets stringent environmental standards for natural gas pool heaters.

• Compact Footprint – designed for efficient equipment-pad placement without sacrificing performance.

• Electronic Ignition with Safety Features – ensures reliable start-up and includes pressure/lower-limit sensing for safe operation.

Customer-Facing Q&A

Q: Is this heater only compatible with natural gas?
A: Yes — this model is specified for natural gas fuel. Be sure to confirm gas-type compatibility before installation.
Q: Will this fit my existing plumbing and pad layout?
A: Likely, but always check your system’s water-flow rate, pipe size, venting requirements and equipment-pad footprint for proper fit.
Q: Is this unit suitable for a saltwater system?
A: Yes — because of its corrosion-resistant heat exchanger, it is well-suited for salt pool applications when properly maintained.
Q: What if my pool isn’t very large—do I need a 400 K BTU unit?
A: Perhaps not. This heater delivers high capacity, so for smaller pools a lower BTU model may offer sufficient performance and better efficiency.
Q: How do I maintain it for long life?
A: Regular inspections of plumbing, proper chemistry, annual checks of the heat exchanger and ensuring forwarding flow all contribute to longevity and optimal performance.