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Expansion Tanks

  • #30 Extrol Expansion Tank (4.4 Gallon)
    SKU: 102-1
    Brand: Amtrol
    (216)
    $38.45 each
    $147.80 box of 4
    $36.95 each
    634
    Tue, Apr 2
    634
    QtyArrives
    634 Tue, Apr 2
    Questions? Call 1-888-757-4774
  • #15 Extrol Expansion Tank (2 Gallon)
    SKU: 101-1
    Brand: Amtrol
    (58)
    $31.95 each
    $122.60 box of 4
    $30.65 each
    492
    Tue, Apr 2
    492
    QtyArrives
    492 Tue, Apr 2
    Questions? Call 1-888-757-4774
  • #60 Extrol Expansion Tank (7.6 Gallon)
    SKU: 103-1
    Brand: Amtrol
    (28)
    $65.85 each
    $253.00 box of 4
    $63.25 each
    128
    Tue, Apr 2
    128
    QtyArrives
    128 Tue, Apr 2
    Questions? Call 1-888-757-4774
  • $19.95 each
    $191.50 box of 10
    $19.15 each
    123
    Tue, Apr 2
    623
    QtyArrives
    123 Tue, Apr 2
    500 Tue, Apr 2 – Wed, Apr 3
    Questions? Call 1-888-757-4774
  • 11" HydroClaw Expansion Tank Support Bracket
    SKU: HC11-A
    Brand: Storm King Enterprises
    (39)
    $40.95 each
    60
    Tue, Apr 2
    60
    QtyArrives
    60 Tue, Apr 2
    Questions? Call 1-888-757-4774
  • $14.85 each
    $142.50 box of 10
    $14.25 each
    101
    Tue, Apr 2
    101
    QtyArrives
    101 Tue, Apr 2
    Questions? Call 1-888-757-4774
  • $17.25 each
    $165.50 box of 10
    $16.55 each
    122
    Tue, Apr 2
    122
    QtyArrives
    122 Tue, Apr 2
    Questions? Call 1-888-757-4774
  • 8" HydroClaw Expansion Tank Support Bracket
    SKU: HC8-B
    Brand: Storm King Enterprises
    (24)
    $30.95 each
    8
    Tue, Apr 2
    8
    QtyArrives
    8 Tue, Apr 2
    Questions? Call 1-888-757-4774
  • $39.55 each
    $379.50 box of 10
    $37.95 each
    98
    Tue, Apr 2
    98
    QtyArrives
    98 Tue, Apr 2
    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
    92
    Tue, Apr 2
    92
    QtyArrives
    92 Tue, Apr 2
    Questions? Call 1-888-757-4774
  • Model 110 Fill-Trol w/ Valve (4.4 Gallon)
    SKU: 110-1
    Brand: Amtrol
    (34)
    $85.65 each
    $329.00 box of 4
    $82.25 each
    75
    Tue, Apr 2
    75
    QtyArrives
    75 Tue, Apr 2
    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
    8
    Tue, Apr 2
    8
    QtyArrives
    8 Tue, Apr 2
    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
    15
    Tue, Apr 2
    15
    QtyArrives
    15 Tue, Apr 2
    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
    36
    Tue, Apr 2
    36
    QtyArrives
    36 Tue, Apr 2
    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
    44
    Tue, Apr 2
    44
    QtyArrives
    44 Tue, Apr 2
    Questions? Call 1-888-757-4774
  • SX-40V Extrol Expansion Tank (20 Gallon)
    SKU: 118-78
    Brand: Amtrol
    (9)
    $164.95 each
    $475.05 box of 3
    $158.35 each
    20
    Tue, Apr 2
    20
    QtyArrives
    20 Tue, Apr 2
    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
    Mon, Apr 22 – Mon, Apr 29
    Arrives
    Mon, Apr 22 – Mon, Apr 29
    Questions? Call 1-888-757-4774 or
  • Fill Control Valve
    SKU: 109-15
    Brand: Amtrol
    (7)
    $43.55 each
    $167.40 box of 4
    $41.85 each
    43
    Tue, Apr 2
    43
    QtyArrives
    43 Tue, Apr 2
    Questions? Call 1-888-757-4774
  • $37.35 each
    $358.50 box of 10
    $35.85 each
    14
    Tue, Apr 2
    14
    QtyArrives
    14 Tue, Apr 2
    Questions? Call 1-888-757-4774
  • RX-15 Radiant Extrol Expansion Tank (2 Gallon)
    SKU: 140-705
    Brand: Amtrol
    (6)
    $57.75 each
    $221.80 box of 4
    $55.45 each
    26
    Tue, Apr 2
    26
    QtyArrives
    26 Tue, Apr 2
    Questions? Call 1-888-757-4774
  • $78.95 each
    $379.75 box of 5
    $75.95 each
    44
    Tue, Apr 2
    44
    QtyArrives
    44 Tue, Apr 2
    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
    1
    Tue, Apr 2
    1
    QtyArrives
    1 Tue, Apr 2
    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
    24
    Tue, Apr 2
    24
    QtyArrives
    24 Tue, Apr 2
    Questions? Call 1-888-757-4774
  • $66.95 each
    12
    Tue, Apr 2
    12
    QtyArrives
    12 Tue, Apr 2
    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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