Expansion Tanks

  • #30 Extrol Expansion Tank (4.4 Gallon)
    SKU: 102-1
    Brand: Amtrol
    (210)
    $38.45 each
    $147.80 box of 4
    $36.95 each
    1,132
    Thu, Feb 28
    1,132
    QtyArrives
    1,132 Thu, Feb 28
    Questions? Call 1-888-757-4774
  • #15 Extrol Expansion Tank (2 Gallon)
    SKU: 101-1
    Brand: Amtrol
    (56)
    $31.95 each
    $122.60 box of 4
    $30.65 each
    728
    Thu, Feb 28
    728
    QtyArrives
    728 Thu, Feb 28
    Questions? Call 1-888-757-4774
  • #60 Extrol Expansion Tank (7.6 Gallon)
    SKU: 103-1
    Brand: Amtrol
    (27)
    $65.85 each
    $253.00 box of 4
    $63.25 each
    254
    Thu, Feb 28
    254
    QtyArrives
    254 Thu, Feb 28
    Questions? Call 1-888-757-4774
  • $19.95 each
    $191.50 box of 10
    $19.15 each
    120
    Thu, Feb 28
    620
    QtyArrives
    120 Thu, Feb 28
    500 Fri, Mar 1 – Mon, Mar 4
    Questions? Call 1-888-757-4774
  • 11" HydroClaw Expansion Tank Support Bracket
    SKU: HC11-A
    Brand: Storm King Enterprises
    (37)
    $40.95 each
    58
    Thu, Feb 28
    58
    QtyArrives
    58 Thu, Feb 28
    Questions? Call 1-888-757-4774
  • $14.85 each
    $142.50 box of 10
    $14.25 each
    135
    Thu, Feb 28
    135
    QtyArrives
    135 Thu, Feb 28
    Questions? Call 1-888-757-4774
  • $17.25 each
    $165.50 box of 10
    $16.55 each
    135
    Thu, Feb 28
    135
    QtyArrives
    135 Thu, Feb 28
    Questions? Call 1-888-757-4774
  • $39.55 each
    $379.50 box of 10
    $37.95 each
    132
    Thu, Feb 28
    132
    QtyArrives
    132 Thu, Feb 28
    Questions? Call 1-888-757-4774
  • 8" HydroClaw Expansion Tank Support Bracket
    SKU: HC8-B
    Brand: Storm King Enterprises
    (23)
    $30.95 each
    26
    Thu, Feb 28
    26
    QtyArrives
    26 Thu, Feb 28
    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
    145
    Thu, Feb 28
    145
    QtyArrives
    145 Thu, Feb 28
    Questions? Call 1-888-757-4774
  • Model 110 Fill-Trol w/ Valve (4.4 Gallon)
    SKU: 110-1
    Brand: Amtrol
    (33)
    $85.65 each
    $329.00 box of 4
    $82.25 each
    98
    Thu, Feb 28
    98
    QtyArrives
    98 Thu, Feb 28
    Questions? Call 1-888-757-4774
  • SX-30V Extrol Expansion Tank (14 Gallon)
    SKU: 118-27
    Brand: Amtrol
    (6)
    $135.95 each
    $391.65 box of 3
    $130.55 each
    48
    Thu, Feb 28
    48
    QtyArrives
    48 Thu, Feb 28
    Questions? Call 1-888-757-4774
  • RX-30 Radiant Extrol Expansion Tank (4.4 Gallon)
    SKU: 141-305
    Brand: Amtrol
    (10)
    $70.45 each
    $270.60 box of 4
    $67.65 each
    61
    Thu, Feb 28
    61
    QtyArrives
    61 Thu, Feb 28
    Questions? Call 1-888-757-4774
  • Model 109 Fill-Trol w/ Valve (2 Gallon)
    SKU: 109-1
    Brand: Amtrol
    (15)
    $69.95 each
    $268.60 box of 4
    $67.15 each
    47
    Thu, Feb 28
    47
    QtyArrives
    47 Thu, Feb 28
    Questions? Call 1-888-757-4774
  • #90 Extrol Expansion Tank (14 Gallon)
    SKU: 112-1
    Brand: Amtrol
    (10)
    $114.95 each
    $441.40 box of 4
    $110.35 each
    58
    Thu, Feb 28
    58
    QtyArrives
    58 Thu, Feb 28
    Questions? Call 1-888-757-4774
  • SX-40V Extrol Expansion Tank (20 Gallon)
    SKU: 118-78
    Brand: Amtrol
    (8)
    $164.95 each
    $475.05 box of 3
    $158.35 each
    46
    Thu, Feb 28
    46
    QtyArrives
    46 Thu, Feb 28
    Questions? Call 1-888-757-4774
  • SX-60V Extrol Expansion Tank (32 Gallon)
    SKU: 118-79
    Brand: Amtrol
    (1)
    $215.95 each
    $414.70 box of 2
    $207.35 each
    15
    Thu, Feb 28
    15
    QtyArrives
    15 Thu, Feb 28
    Questions? Call 1-888-757-4774
  • Fill Control Valve
    SKU: 109-15
    Brand: Amtrol
    (7)
    $43.55 each
    $167.40 box of 4
    $41.85 each
    54
    Thu, Feb 28
    54
    QtyArrives
    54 Thu, Feb 28
    Questions? Call 1-888-757-4774
  • $37.35 each
    $358.50 box of 10
    $35.85 each
    51
    Thu, Feb 28
    51
    QtyArrives
    51 Thu, Feb 28
    Questions? Call 1-888-757-4774
  • RX-15 Radiant Extrol Expansion Tank (2 Gallon)
    SKU: 140-705
    Brand: Amtrol
    (5)
    $57.75 each
    $221.80 box of 4
    $55.45 each
    39
    Thu, Feb 28
    39
    QtyArrives
    39 Thu, Feb 28
    Questions? Call 1-888-757-4774
  • $78.95 each
    $379.75 box of 5
    $75.95 each
    52
    Thu, Feb 28
    52
    QtyArrives
    52 Thu, Feb 28
    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
    11
    Thu, Feb 28
    11
    QtyArrives
    11 Thu, Feb 28
    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
    27
    Thu, Feb 28
    27
    QtyArrives
    27 Thu, Feb 28
    Questions? Call 1-888-757-4774
  • $66.95 each
    21
    Thu, Feb 28
    21
    QtyArrives
    21 Thu, Feb 28
    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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