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Rheem / Raypak 266A-MN ASME 266,000 BTU Millivolt Natural Gas Heater

  • Millivolt Ignition
  • Copper Tube Bundle
  • Bronze Headers
  • ASME
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SKU: RHM 266MNASME Category:


Enjoy your pool……Extend your swim season
Your pool and spa is a long-term investment that you, your family and friends will enjoy year after year. Now, there’s an easier way to enjoy that investment more often, more reliably and more efficiently throughout the year…the Rheem Millivolt pool and spa heater.

Think about being able to use your pool or spa at the perfect comfort level even when Fall arrives…or when the first chill of Winter is felt in the wind…or in the Spring or Summer when evenings can turn chilly in a minute! Helping you get more enjoyment from your pool or spa is the smart idea behind the Raypak Millivolt.

Indoor Vent Hood Available for an additional $126.96

** OVERSIZED – Call or email for freight or metro Denver delivery quote **




Simple Controls
• Mechanical Thermostat
The Rheem Millivolt gas heater comes with one mechanical thermostat. This control allows you to set your pool or spa temperature precisely at your favorite setting. Just set it, and forget it! Truly simple.

Wind Resistant
• The Rheem Millivolt has the best outdoor design in the market today. With over 50 years in designing and building gas heaters, Raypak has put all that experience into its newest design. No need for fans to combat drafting problems, the Raypak millivolt was designed for outdoor installations with its exclusive low profile design. It is so thoughtfully and carefully designed it actually protects itself from the things that tend to stifle ordinary pool and spa heaters: falling leaves, wind, airborne debris, rain, downdrafts, updrafts, sleet, snow, etc. In fact it is so efficiently designed it ensures uninterrupted heating performance regardless of all but the most extreme weather conditions. Built Raypak tough. Built to last.

• Smart Design
One look will tell you that the Raypak Millivolt is different! The look is contemporary. The design is advanced. And inside and out it’s engineered to last. The attractive forest green and charcoal gray panels complement the latest pool and spa equipment designs. Rheem’s original “pagoda top” design will keep the heater operating even in extreme wind conditions and downdrafts.
• Polytuff Powder Coating
The Rheem Millivolt has a polyester coated, non-corrosive cabinet that is more durable than solventborne and waterborne coated metal cabinets. Every piece of sheet metal that gets powder coated goes through a 7-stage wash system making certain the powder paint has a perfect bond. Underneath the tough and beautiful finish you will find galvanized metal that offers superior rust prevention and years of durable service.
Non-Corrosive Waterways
• Polymer Header
The Rheem Millivolt incorporates the latest in header design technology. Rheem’s state-of-the-art engineering department utilized the latest in 3-D computer aided design to engineer the part for optimal performance. Polymer resin headers prevent rust stains from harming your pools surface giving you years of trouble-free swimming pleasure
• All Copper Fin Tube Heat Exchanger
All Rheem Millivolt gas heaters come standard with integral copper finned tube. This means that the fin tubing is made from one piece of extruded copper tube. Since the fins are integral to the tube, maximum heat transfer is attained. Every Rheem Millivolt has the same robust design tube bundle that we use in our large gas commercial boilers.
• Stainless Steel Tube Sheet
Stainless steel tube sheets are used on all Rheem Millivolt heaters that use the Polymer resin headers. This allows for a completely nonferrous waterway leaving your pool truly rust-free.
• CPVC 2″ Water Connections
Standard with every Rheem Millivolt is a set of 2″ slip fit CPVC water connections to make your installation secure and effortless.
• Condensation Protection
Standard on all Raypak Millivolt models is Rheem’s Unitherm Governor, which helps reduce condensation from low inlet water temperatures. The Unitherm Governor automatically regulates the water flow to help keep the water temperature in the heat exchanger above 105°. Both water temperature and water flow rate are controlled to eliminate condensation, sooting, and scale buildup that can shorten heater life.

• High Flow Rates
No need to worry about large pumps or high flow systems. The Rheem Millivolt comes with an automatic bypass built into the header. You’ll find that the Raypak Millivolt delivers the industry’s lowest pressure drop and highest water flow rate – up to 125 gallons per minute – exceeding the maximum recommended for 2″ plumbing systems. More hot water moves through faster and more efficiently.
• Fuel Efficient
Efficient? You bet. Energy-smart Rheem heaters consistently achieve the highest efficiency ratings and the Raypak Millivolt is no exception. It exceeds all federal and state standards.

Combustion Chamber
• Burner Tray
Every Rheem Millivolt burner tray is built to last. From the stainless steel burners to the aluminized metal used in the heat sensitive areas. In the event that anything should happen to your burners they can be quickly and easily serviced. One more reason why the Rheem Millivolt is made to take the work load year after year.

• Fire Tile
A ceramic fiber combustion box keeps your Rheem Millivolt running efficiently and keeps the outside jacket cool. By using this space-age material the heater won’t retain residual heat after it is turned off, allowing it to be installed without the use of costly metal heat sinks.

• ISO 9001
Rheem is proud to be a ISO 9001 registered manufacturing plant. One more reason why Raypak is number one in the heater industry today.
• End-of-Line Test
Every Rheem gas pool heater is plumbed and test fired before it is put in the carton. This ensures that your heater will fire right out of the box and continue to give you years of trouble-free operation.
• Quality Checkpoints
The Rheem assembly process includes 6 final assembly quality checkpoints that help to ensure that each and every Rheem Millivolt is built correctly, and built to last.
• CSA Certified
All of Rheem products are CSA certified. The Rheem Millivolt is tested by CSA to the ANSI Z21.56 standard.

Rheem / Raypak 266A-MN ASME 266,000 BTU Millivolt Natural Gas Heater

Additional information

Weight 3360 oz
Dimensions 50 × 50 × 50 in
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