Pentair MasterTemp 461021 400K BTU heavy duty ASME natural gas pool heaterPentair MasterTemp Digital IID Heavy Duty ASME Natural Gas Low NOx Heater 400K BTU, 461021 In stock$5,17999
Pentair MasterTemp 461021 400K BTU heavy duty ASME natural gas pool heater
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Pentair MasterTemp Digital IID Heavy Duty ASME Natural Gas Low NOx Heater 400K BTU, 461021

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$5,17999
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Quick overview

  • Read this first ASME MasterTemps no longer include tubes and unions, and they cannot be bought separately. Order only if you are keeping the hookups from a previous Pentair ASME heater.
  • Heavy duty cupro-nickel the HD exchanger is built for low pH, high flow and heavy use, the conditions that wear out a standard exchanger.
  • 400,000 BTU natural gas the 400K natural gas model with a low NOx burner.
  • ASME version for installations that require an ASME stamped heater.
  • Digital IID controls electronic ignition with indicator lights that show what the heater is doing at a glance.
  • Compact and quiet a small footprint and quiet operation that stays out of the way of the pool.
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Product details

The Pentair 461021 is the MasterTemp 400 in its heavy duty ASME form: a 400,000 BTU natural gas pool and spa heater with digital intermittent ignition, a low NOx burner and a cupro-nickel heat exchanger. It is the MasterTemp for installations that call for an ASME stamped heater and for water that is hard on equipment.

Before you order

Pentair no longer supplies tubes and unions with the ASME MasterTemp models, and they are not available to purchase separately. Order this heater only if you are certain you have the hookups that came with your previous Pentair ASME heater.

Heavy duty by design

The HD exchanger uses cupro-nickel tubing that stands up to low pH, high flow and heavy use, the conditions that shorten the life of a standard copper exchanger. The rest of the heater is the MasterTemp you know: as simple to run as a home furnace, with indicator lights that make operation and monitoring obvious, in a compact cabinet that runs quietly enough not to intrude on the pool.

Delivery

This is a freight item and ships on a pallet. Inspect it on arrival and note any damage before signing.

Specifications
Brand Pentair
Manufacturer part number 461021
UPC 788379858278
Model MasterTemp
Type Pool and spa heater
Fuel Natural gas
Input 400,000 BTU
Ignition Digital IID
Emissions Low NOx
Heat exchanger Cupro-nickel, heavy duty
Certification ASME
Tubes and unions Not included, no longer available separately
Ships Freight

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Questions and answers

What people ask about this product, answered by our pool techs.

Does it come with the plumbing tubes and unions?
No. Pentair stopped supplying tubes and unions with the ASME MasterTemp models, and they are no longer sold separately. Order this heater only if you have the hookups from your previous Pentair ASME heater.
What is the difference between the ASME and standard MasterTemp?
The ASME model is built and certified to the ASME code, which some commercial and public pool installations require. If your pool does not require an ASME stamped heater, the standard MasterTemp 400 is the usual choice.
What is the heavy duty exchanger for?
The HD cupro-nickel exchanger is built for the harshest applications: low pH, high flow rates and heavy use. It lasts where a standard exchanger would not.
How does it ship?
By freight on a pallet. Have someone there to inspect the carton and sign, and note any damage on the bill of lading before the driver leaves.
Ask your own question