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Expansion Tanks

  • #30 Extrol Expansion Tank (4.4 Gallon)
    SKU: 102-1
    Brand: Amtrol
    (223)
    $38.45 each
    $147.80 box of 4
    $36.95 each
    1,874
    Thu, Jun 27
    1,874
    QtyArrives
    1,874 Thu, Jun 27
    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
    547
    Thu, Jun 27
    547
    QtyArrives
    547 Thu, Jun 27
    Questions? Call 1-888-757-4774
  • #60 Extrol Expansion Tank (7.6 Gallon)
    SKU: 103-1
    Brand: Amtrol
    (29)
    $65.85 each
    $253.00 box of 4
    $63.25 each
    163
    Thu, Jun 27
    163
    QtyArrives
    163 Thu, Jun 27
    Questions? Call 1-888-757-4774
  • $22.29 each
    $213.90 box of 10
    $21.39 each
    105
    Thu, Jun 27
    287
    QtyArrives
    105 Thu, Jun 27
    182 Fri, Jun 28 – Mon, Jul 1
    Questions? Call 1-888-757-4774
  • 11" HydroClaw Expansion Tank Support Bracket
    SKU: HC11-A
    Brand: Storm King Enterprises
    (42)
    $40.95 each
    49
    Thu, Jun 27
    49
    QtyArrives
    49 Thu, Jun 27
    Questions? Call 1-888-757-4774
  • $14.85 each
    $142.50 box of 10
    $14.25 each
    121
    Thu, Jun 27
    121
    QtyArrives
    121 Thu, Jun 27
    Questions? Call 1-888-757-4774
  • $17.25 each
    $165.50 box of 10
    $16.55 each
    119
    Thu, Jun 27
    119
    QtyArrives
    119 Thu, Jun 27
    Questions? Call 1-888-757-4774
  • Flexconsole - 1/2" x 1/2" NPT - Steel (Red)
    Contains Lead
    SKU: 97975
    Brand: Flamco
    (7)
    $22.95 each
    67
    Thu, Jun 27
    67
    QtyArrives
    67 Thu, Jun 27
    Questions? Call 1-888-757-4774
  • 8" HydroClaw Expansion Tank Support Bracket
    SKU: HC8-B
    Brand: Storm King Enterprises
    (24)
    $30.95 each
    85
    Thu, Jun 27
    85
    QtyArrives
    85 Thu, Jun 27
    Questions? Call 1-888-757-4774
  • $39.55 each
    $379.50 box of 10
    $37.95 each
    178
    Thu, Jun 27
    178
    QtyArrives
    178 Thu, Jun 27
    Questions? Call 1-888-757-4774
  • Model 110 Fill-Trol w/ Valve (4.4 Gallon)
    SKU: 110-1
    Brand: Amtrol
    (35)
    $85.65 each
    $329.00 box of 4
    $82.25 each
    98
    Thu, Jun 27
    98
    QtyArrives
    98 Thu, Jun 27
    Questions? Call 1-888-757-4774
  • SX-30V Extrol Expansion Tank (14 Gallon)
    SKU: 118-27
    Brand: Amtrol
    (7)
    $135.95 each
    $391.65 box of 3
    $130.55 each
    77
    Thu, Jun 27
    77
    QtyArrives
    77 Thu, Jun 27
    Questions? Call 1-888-757-4774
  • Model 109 Fill-Trol w/ Valve (2 Gallon)
    SKU: 109-1
    Brand: Amtrol
    (16)
    $69.95 each
    $268.60 box of 4
    $67.15 each
    64
    Thu, Jun 27
    64
    QtyArrives
    64 Thu, Jun 27
    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
    78
    Thu, Jun 27
    78
    QtyArrives
    78 Thu, Jun 27
    Questions? Call 1-888-757-4774
  • SX-40V Extrol Expansion Tank (20 Gallon)
    SKU: 118-78
    Brand: Amtrol
    (10)
    $164.95 each
    $475.05 box of 3
    $158.35 each
    58
    Thu, Jun 27
    58
    QtyArrives
    58 Thu, Jun 27
    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
    40
    Thu, Jun 27
    40
    QtyArrives
    40 Thu, Jun 27
    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
    31
    Thu, Jun 27
    31
    QtyArrives
    31 Thu, Jun 27
    Questions? Call 1-888-757-4774
  • Fill Control Valve
    SKU: 109-15
    Brand: Amtrol
    (8)
    $43.55 each
    $167.40 box of 4
    $41.85 each
    34
    Thu, Jun 27
    34
    QtyArrives
    34 Thu, Jun 27
    Questions? Call 1-888-757-4774
  • RBFF, 1/2" Residential Boiler Fill Fitting
    SKU: 0386466
    Brand: Watts
    (4)
    $64.75 each
    $309.75 box of 5
    $61.95 each
    92
    Thu, Jun 27
    92
    QtyArrives
    92 Thu, Jun 27
    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
    13
    Thu, Jun 27
    13
    QtyArrives
    13 Thu, Jun 27
    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
    26
    Thu, Jun 27
    26
    QtyArrives
    26 Thu, Jun 27
    Questions? Call 1-888-757-4774
  • $66.95 each
    13
    Thu, Jun 27
    13
    QtyArrives
    13 Thu, Jun 27
    Questions? Call 1-888-757-4774
  • $37.35 each
    $358.50 box of 10
    $35.85 each
    66
    Thu, Jun 27
    66
    QtyArrives
    66 Thu, Jun 27
    Questions? Call 1-888-757-4774
  • $78.95 each
    $379.75 box of 5
    $75.95 each
    59
    Thu, Jun 27
    59
    QtyArrives
    59 Thu, Jun 27
    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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