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FREE USPS GROUND ADVANTAGE SHIPPING on items OVER $75.00 (UNDER 1 LB.) based on the weight per item. If you can't find a part you are looking for, call or text us at 970-518-3085!
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!

Small Filler Neck - TNX-NEC-FLL

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Original price $76.85
Original price $76.85 - Original price $76.85
Original price $76.85
Current price $61.48
$61.48 - $61.48
Current price $61.48

The Small Filler Neck is a direct replacement part used in Aqua-Hot & Hydro-Hot hydronic heating systems to connect the expansion tank to the fill cap or service port. This component allows easy refilling and inspection of antifreeze fluid levels in the system.

Important Information
  • Connects to Expansion Tank – Acts as the upper filler port for topping off antifreeze or inspecting fluid condition.
  • Durable Construction – Built to handle temperature fluctuations and chemical exposure from glycol-based antifreeze.
  • Genuine OEM Replacement – Designed for perfect compatibility and optimal performance in Aqua-Hot & Hydro-Hot heating systems.
WARNING: CRITICAL COMPONENT – IMPROPER REPLACEMENT CAN LEAD TO SYSTEM MELTDOWN!

Compatible Models

Aqua-Hot
AHE-100-00S AHE-100-01S AHE-100-02S AHE-100-03S AHE-100-04S
AHE-101-000 AHE-120-03X AHE-120-04X AHE-130-03X AHE-130-04X
AHE-200-02S AHE-450-DE1 AHE-450-DM1 AHE-600-D01 AHE-600-D02
AHE-675-D01 AHE-675-D02 AHE-920-431 431/11 431/11B
431/12
Hydro-Hot
HHE-200-01E HHE-200-02E HHE-200-03E HHE-200-04E HHE-200-05E
HHE-500-01M HHE-500-02M HHE-500-03M HHE-500-04M HHE-500-05M
HHE-200-06E HHE-200-07E HHE-200-08E HHE-200-09E 2001-E
HHE-500-06M HHE-500-07M HHE-500-08M HHE-500-09M HHE-102-0EE
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