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FREE USPS GROUND ADVANTAGE SHIPPING on items OVER $75.00 (UNDER 1 LB.) based on weight per item. If you can't find a part you are looking for, call or text us at 970-518-3085! Holiday Notice: Please be advised that we will be closed for the holidays on December 24–26, 2025, and December 31, 2025 through January 2, 2026.
Model 250D (Diesel) - AHE-250-D02

Model 250D (Diesel) - AHE-250-D02

by Aqua-Hot
Save 9% Save 8%
$6,220.35
$6,220.35 - $8,478.18
$6,220.35
$5,722.72
$5,722.72 - $7,754.77
$5,722.72

The Aqua-Hot 250D (Diesel) Hydronic Heating Systems are used in towable RVs and smaller motorhomes to deliver continuous on-demand hot water and interior comfort heat. The 250D is a diesel-fueled system designed for efficient, quiet operation in compact spaces. REPLACEMENT HEATER FOR AHE-250-D01 & AHE-250-D02

Important Information:
  • All-in-One Heating Solution – Provides both interior heat and continuous domestic hot water through a single, integrated system.
  • Recommended Antifreeze Replacement – Requires approximately 7 gallons of red or green antifreeze.
    Click here to purchase antifreeze separately
Heater Includes:
  • 250D Aqua-Hot System
  • 2-Year Warranty
WARNING: PROFESSIONAL INSTALLATION RECOMMENDED
Installation Item List Below
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***  2 Week Lead Time Not Including Shipping Days ***

PRODUCT SPEC SHEET, MANUALS & GUIDES

Ultra-Compact Hydronic Heating

Ultra-Compact Hydronic Heating

  • Single, self-contained unit: Delivers residential-style interior heating using heat exchangers and/or in floor heat with the ability to deliver a luxurious supply of continuous hot water at
    110ºF-120ºF at a rate of 1.5 gallons per minute. It’s just like the luxury comfort in a traditional home or high-end diesel motorhome.
  • Quiet: Low voltage fans provide an almost completely noise free operation.
  • Fast Installs: Heating, domestic water, and fuel supply/outlet ports are located on top of the tank for easy connection access. Integrated Mounting tray facilitates air intake and exhaust.
  • Easy Operation: Heat controlled by your thermostat andendless hot water by simply turning on a faucet.
Installation Kit Includes 
  • 1-1/2" Black Exhaust Fittings Kit – Quantity: 1
  • 3 Quart Expansion Bottle with Sensor – Quantity: 1
  • 2-Position Switch Panel Assembly – Quantity: 1
  • Cozy III Heat Exchanger – Quantity: 5
  • 5/8" Red Oxygen Barrier PEX Tubing (100 ft) – Quantity: 2
  • 5/8" Polytube Bend Support – Quantity: 5
  • Constant Tension Hose Clamp, 3/4" – Quantity: 18
  • Modified Brass Insert Fitting – Quantity: 12
  • Low Temperature Thermostat Assembly – Quantity: 1
  • Room Thermostat with Positive Off – Quantity: 1
  • Cozy Grille, 10" x 2" – Quantity: 5

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