Family Owned & Operated Since 1946

Frederick Bros. can offer you an extensive range of Rinnai products for a variety of heating, hot water, and cooking needs. We are a Full Service Company, so we do not just sell & install the product... we are there for you as a service provider year after year. If your system uses Liquid Propane, we can also provide you with your delivery needs as well. See our Propane page for more details.

"...thank you all for your service. I could always count on your help...exceptional service much appreciated."

Rinnai Propane & Natural Gas Heaters

Rinnai heaters are an affordable, energy efficient solution to heating any size room.

Benefits at a glance

  • intelligent heating with up to 82% AFUE efficiency saves energy
  • Modulating gas valve and variable-speed blower for consistent heat
  • Programmable thermostat with timer function and child safety lock
  • Easy installation requires no ductwork
  • Durable stainless steel heat exchanger for reliable comfort
  • On-board self-diagnostic for easy trouble shooting
  • Auto restart for power outages
  • Setback with frost protection
  • Cool-to-the-touch Cabinet
  • Sealed combustion maintains indoor air quality


Rinnai EX-38

  • 1300-1500 sq/ft
  • Max BTU rating - 38,400
  • Dimensions = 26"H x 36"W x 13"D


Rinnai EX-22

  • 700-900 sq/ft
  • Max BTU rating - 21,500
  • Dimensions = 22.875"H x 29.875"W x 10.125"D


Rinnai EX-17

  • 400-700 sq/ft
  • Max BTU rating - 16,700
  • Dimensions = 22.875"H x 29.875"W x 10.125"D


Rinnai EX-11

  • 300 sq/ft
  • Max BTU rating - 11,000
  • Dimensions = 27.375"H x 18.25 "W x 10.125"D


Rinnai EX-08

  • 200 sq/ft
  • Max BTU rating - 8,000
  • Dimensions = 27.375"H x 18.25 "W x 10.125"D

Continuum (Hot Water)

Rinnai Continuum (Hot Water)

An endless supply of hot water, whenever you need it—even for multiple tasks at the same time. Tankless Water Heaters revolutionize comfort, energy efficiency and convenience.

164 U.S. Rt. 1
Scarborough Maine, 04074
Office hours
8am to 4:30pm
(Monday thru Friday )
Best of the Best

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Service Contract Plans

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Propane Terms & Conditions
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