Expansion Tanks

  • #30 Extrol Expansion Tank (4.4 Gallon)
    SKU: 102-1
    Brand: Amtrol
    (210)
    $35.95 each
    $137.80 box of 4
    $34.45 each
    2,174
    Mon, Feb 4
    2,174
    QtyArrives
    2,174 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • #15 Extrol Expansion Tank (2 Gallon)
    SKU: 101-1
    Brand: Amtrol
    (56)
    $29.95 each
    $115.00 box of 4
    $28.75 each
    763
    Mon, Feb 4
    763
    QtyArrives
    763 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • #60 Extrol Expansion Tank (7.6 Gallon)
    SKU: 103-1
    Brand: Amtrol
    (27)
    $61.65 each
    $235.80 box of 4
    $58.95 each
    373
    Mon, Feb 4
    373
    QtyArrives
    373 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • $19.45 each
    $186.50 box of 10
    $18.65 each
    177
    Mon, Feb 4
    677
    QtyArrives
    177 Mon, Feb 4
    500 Tue, Feb 5 – Wed, Feb 6
    Questions? Call 1-888-757-4774
  • 11" HydroClaw Expansion Tank Support Bracket
    SKU: HC11-A
    Brand: Storm King Enterprises
    (37)
    $40.95 each
    95
    Mon, Feb 4
    95
    QtyArrives
    95 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • $14.85 each
    $142.50 box of 10
    $14.25 each
    157
    Mon, Feb 4
    157
    QtyArrives
    157 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • $17.25 each
    $165.50 box of 10
    $16.55 each
    154
    Mon, Feb 4
    154
    QtyArrives
    154 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • $39.55 each
    $379.50 box of 10
    $37.95 each
    143
    Mon, Feb 4
    143
    QtyArrives
    143 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • 8" HydroClaw Expansion Tank Support Bracket
    SKU: HC8-B
    Brand: Storm King Enterprises
    (23)
    $30.95 each
    44
    Mon, Feb 4
    44
    QtyArrives
    44 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • Flexconsole - 1/2" x 1/2" NPT - Steel (Red)
    Contains Lead
    SKU: 97975
    Brand: Flamco
    (6)
    $22.95 each
    188
    Mon, Feb 4
    188
    QtyArrives
    188 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • Model 110 Fill-Trol w/ Valve (4.4 Gallon)
    SKU: 110-1
    Brand: Amtrol
    (33)
    $79.95 each
    $307.80 box of 4
    $76.95 each
    133
    Mon, Feb 4
    133
    QtyArrives
    133 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • SX-30V Extrol Expansion Tank (14 Gallon)
    SKU: 118-27
    Brand: Amtrol
    (6)
    $125.95 each
    $359.85 box of 3
    $119.95 each
    78
    Mon, Feb 4
    78
    QtyArrives
    78 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • Model 109 Fill-Trol w/ Valve (2 Gallon)
    SKU: 109-1
    Brand: Amtrol
    (15)
    $63.95 each
    $247.80 box of 4
    $61.95 each
    83
    Mon, Feb 4
    83
    QtyArrives
    83 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • RX-30 Radiant Extrol Expansion Tank (4.4 Gallon)
    SKU: 141-305
    Brand: Amtrol
    (10)
    $65.95 each
    $251.80 box of 4
    $62.95 each
    69
    Mon, Feb 4
    69
    QtyArrives
    69 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • #90 Extrol Expansion Tank (14 Gallon)
    SKU: 112-1
    Brand: Amtrol
    (10)
    $105.95 each
    $399.80 box of 4
    $99.95 each
    82
    Mon, Feb 4
    82
    QtyArrives
    82 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • SX-40V Extrol Expansion Tank (20 Gallon)
    SKU: 118-78
    Brand: Amtrol
    (8)
    $149.95 each
    $431.85 box of 3
    $143.95 each
    66
    Mon, Feb 4
    66
    QtyArrives
    66 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • SX-60V Extrol Expansion Tank (32 Gallon)
    SKU: 118-79
    Brand: Amtrol
    (1)
    $212.95 each
    $407.90 box of 2
    $203.95 each
    33
    Mon, Feb 4
    33
    QtyArrives
    33 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • Fill Control Valve
    SKU: 109-15
    Brand: Amtrol
    (7)
    $39.95 each
    $153.40 box of 4
    $38.35 each
    71
    Mon, Feb 4
    71
    QtyArrives
    71 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • $37.35 each
    $358.50 box of 10
    $35.85 each
    25
    Mon, Feb 4
    25
    QtyArrives
    25 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • $78.95 each
    $379.75 box of 5
    $75.95 each
    58
    Mon, Feb 4
    58
    QtyArrives
    58 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • RX-15 Radiant Extrol Expansion Tank (2 Gallon)
    SKU: 140-705
    Brand: Amtrol
    (5)
    $53.95 each
    $207.80 box of 4
    $51.95 each
    37
    Mon, Feb 4
    37
    QtyArrives
    37 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • RBFF, 1/2" Residential Boiler Fill Fitting
    SKU: 0386466
    Brand: Watts
    (3)
    $64.75 each
    $309.75 box of 5
    $61.95 each
    13
    Mon, Feb 4
    13
    QtyArrives
    13 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • $66.95 each
    23
    Mon, Feb 4
    23
    QtyArrives
    23 Mon, Feb 4
    Questions? Call 1-888-757-4774
  • 1/2" External NPT Heating Expansion Tank (4.4 Gallon)
    SKU: TK300-30
    Brand: Honeywell-Sparco
    (1)
    $42.45 each
    25
    Mon, Feb 4
    25
    QtyArrives
    25 Mon, Feb 4
    Questions? Call 1-888-757-4774

Resources

Videos

Articles

  • An expansion tank is designed to relieve pressure in both a potable water and closed heating system. An expansion tank ensures a constant pressure is maintained within the pipes so they do not get damaged from excess pressure.

    An expansion tank has two parts which are divided by a rubber diaphragm. The top portion of the tank is connected to the hot water system and is filled with water. The bottom portion is filled with air set at approximately 12 psi. As the hot water system is turned on or off, pressure increases. As pressure increases, the diaphragm in the expansion tank is pushed down. This compresses the air in the tank, creating more space for excess water to enter. This relieves excess pressure in the system and prevents pipes in the system from being damaged.

    In the event that the diaphragm fails, the tank will completely fill with water. If this occurs, the tank must be replaced immediately. To check if the expansion tank is working properly, simply place your hand on the tank and feel its temperature. The top portion of the tank should feel warm to the touch, and the bottom portion of the tank should be room temperature. If the entire tank is warm, it is likely that the tank has completely filled with hot water.

    Expansion tanks have capacities ranging from 2 gallons to several hundred gallons. To determine the size needed for your system, use the Expansion Tank Sizing Calculator.

    We offer a wide selection of Amtrol, Watts, Cash Acme, and Bell & Gossett expansion tanks to suit all of your plumbing and heating needs.
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