Pros, Join Our TradeMaster Program!
Expansion Tanks

Expansion Tanks

  • #30 Extrol EX-30 Expansion Tank (4.4 Gallon) Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    #30 Extrol EX-30 Expansion Tank (4.4 Gallon) 102-1 #30 Extrol EX-30 Expansion Tank (4.4 Gallon)
    SKU: 102-1 Amtrol
    SKU: 102-1
    Brand: Amtrol
    (320)
    $40.21 each
    Not Added to List Icon Add to List
    Added to List Icon List
    2,151
    Tue, Nov 2
    2,151
    QtyArrives
    2,151 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • #15 Extrol EX-15 Expansion Tank (2 Gallon) Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    #15 Extrol EX-15 Expansion Tank (2 Gallon) 101-1 #15 Extrol EX-15 Expansion Tank (2 Gallon)
    SKU: 101-1 Amtrol
    SKU: 101-1
    Brand: Amtrol
    (77)
    $41.95 each
    Not Added to List Icon Add to List
    Added to List Icon List
    1,440
    Tue, Nov 2
    1,440
    QtyArrives
    1,440 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • #60 Extrol EX-60 Expansion Tank (7.6 Gallon) Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    #60 Extrol EX-60 Expansion Tank (7.6 Gallon) 103-1 #60 Extrol EX-60 Expansion Tank (7.6 Gallon)
    SKU: 103-1 Amtrol
    SKU: 103-1
    Brand: Amtrol
    (44)
    $75.69 each
    Not Added to List Icon Add to List
    Added to List Icon List
    54
    Tue, Nov 2
    54
    QtyArrives
    54 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • 1/2" Pro-Pal Full Port Brass Ball Valve w/ Hi-Flow Hose Drain Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    1/2" Pro-Pal Full Port Brass Ball Valve w/ Hi-Flow Hose Drain 41672 1/2" Pro-Pal Full Port Brass Ball Valve w/ Hi-Flow Hose Drain
    Contains Lead
    SKU: 41672 Webstone
    SKU: 41672
    Brand: Webstone
    (12)
    $24.53 each
    Not Added to List Icon Add to List
    Added to List Icon List
    661
    Tue, Nov 2
    661
    QtyArrives
    661 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • QuickStrap Expansion Tank Mounting Bracket <br>(5 Gal. Capacity) Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    QuickStrap Expansion Tank Mounting Bracket (5 Gal. Capacity) QS-U QuickStrap Expansion Tank Mounting Bracket (5 Gal. Capacity)
    SKU: QS-U Holdrite
    SKU: QS-U
    Brand: Holdrite
    (6)
    $16.77 each
    Not Added to List Icon Add to List
    Added to List Icon List
    896
    Tue, Nov 2
    896
    QtyArrives
    896 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • 11" HydroClaw Expansion Tank Support Bracket Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    11" HydroClaw Expansion Tank Support Bracket HC11-A 11" HydroClaw Expansion Tank Support Bracket
    SKU: HC11-A Storm King Enterprises
    SKU: HC11-A
    Brand: Storm King Enterprises
    (53)
    $45.38 each
    Not Added to List Icon Add to List
    Added to List Icon List
    88
    Tue, Nov 2
    88
    QtyArrives
    88 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • ETX-30, Non-Potable Water Expansion Tank<br>(4.5 Gallon) Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    ETX-30, Non-Potable Water Expansion Tank (4.5 Gallon) 0066606 ETX-30, Non-Potable Water Expansion Tank (4.5 Gallon)
    SKU: 0066606 Watts
    SKU: 0066606
    Brand: Watts
    (20)
    $35.19 each
    Not Added to List Icon Add to List
    Added to List Icon List
    73
    Tue, Nov 2
    73
    QtyArrives
    73 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • 8" HydroClaw Expansion Tank Support Bracket Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    8" HydroClaw Expansion Tank Support Bracket HC8-B 8" HydroClaw Expansion Tank Support Bracket
    SKU: HC8-B Storm King Enterprises
    SKU: HC8-B
    Brand: Storm King Enterprises
    (32)
    $35.70 each
    Not Added to List Icon Add to List
    Added to List Icon List
    256
    Tue, Nov 2
    256
    QtyArrives
    256 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • Model 110 Fill-Trol<br>w/ Valve (4.4 Gallon) Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    Model 110 Fill-Trol w/ Valve (4.4 Gallon) 110-1 Model 110 Fill-Trol w/ Valve (4.4 Gallon)
    SKU: 110-1 Amtrol
    SKU: 110-1
    Brand: Amtrol
    (50)
    $96.33 each
    Not Added to List Icon Add to List
    Added to List Icon List
    166
    Tue, Nov 2
    166
    QtyArrives
    166 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • Nexus Flexconsole - 1/2" x 1/2" NPT - Steel (Red) Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    Nexus Flexconsole - 1/2" x 1/2" NPT - Steel (Red) F97975 Nexus Flexconsole - 1/2" x 1/2" NPT - Steel (Red)
    Contains Lead
    SKU: F97975 Flamco
    SKU: F97975
    Brand: Flamco
    (10)
    $22.95 each
    Not Added to List Icon Add to List
    Added to List Icon List
    249
    Tue, Nov 2
    249
    QtyArrives
    249 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • SX-30V Extrol Expansion Tank (14 Gallon) Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    SX-30V Extrol Expansion Tank (14 Gallon) 118-27 SX-30V Extrol Expansion Tank (14 Gallon)
    SKU: 118-27 Amtrol
    SKU: 118-27
    Brand: Amtrol
    (11)
    $198.10 each
    Not Added to List Icon Add to List
    Added to List Icon List
    93
    Tue, Nov 2
    93
    QtyArrives
    93 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • RX-30 Radiant Extrol Expansion Tank<br>(4.4 Gallon) Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    RX-30 Radiant Extrol Expansion Tank (4.4 Gallon) 141-305 RX-30 Radiant Extrol Expansion Tank (4.4 Gallon)
    SKU: 141-305 Amtrol
    SKU: 141-305
    Brand: Amtrol
    (13)
    $79.37 each
    Not Added to List Icon Add to List
    Added to List Icon List
    109
    Tue, Nov 2
    109
    QtyArrives
    109 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • Model 109 Fill-Trol<br>w/ Valve (2 Gallon) Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    Model 109 Fill-Trol w/ Valve (2 Gallon) 109-1 Model 109 Fill-Trol w/ Valve (2 Gallon)
    SKU: 109-1 Amtrol
    SKU: 109-1
    Brand: Amtrol
    (19)
    $85.46 each
    Not Added to List Icon Add to List
    Added to List Icon List
    199
    Tue, Nov 2
    199
    QtyArrives
    199 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • ETX-60, Non-Potable Water Expansion Tank<br>(6.0 Gallon) Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    ETX-60, Non-Potable Water Expansion Tank (6.0 Gallon) 0066607 ETX-60, Non-Potable Water Expansion Tank (6.0 Gallon)
    SKU: 0066607 Watts
    SKU: 0066607
    Brand: Watts
    (9)
    $61.99 each
    Not Added to List Icon Add to List
    Added to List Icon List
    114
    Tue, Nov 2
    114
    QtyArrives
    114 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • SX-40V Extrol Expansion Tank (20 Gallon) Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    SX-40V Extrol Expansion Tank (20 Gallon) 118-78 SX-40V Extrol Expansion Tank (20 Gallon)
    SKU: 118-78 Amtrol
    SKU: 118-78
    Brand: Amtrol
    (11)
    $236.83 each
    Not Added to List Icon Add to List
    Added to List Icon List
    79
    Tue, Nov 2
    79
    QtyArrives
    79 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • ETX-15, Non-Potable Water Expansion Tank<br>(2.1 Gallon) Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    ETX-15, Non-Potable Water Expansion Tank (2.1 Gallon) 0066605 ETX-15, Non-Potable Water Expansion Tank (2.1 Gallon)
    SKU: 0066605 Watts
    SKU: 0066605
    Brand: Watts
    (2)
    $31.19 each
    Not Added to List Icon Add to List
    Added to List Icon List
    60
    Tue, Nov 2
    60
    QtyArrives
    60 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • SX-60V Extrol Expansion Tank (32 Gallon) Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    SX-60V Extrol Expansion Tank (32 Gallon) 118-79 SX-60V Extrol Expansion Tank (32 Gallon)
    SKU: 118-79 Amtrol
    SKU: 118-79
    Brand: Amtrol
    (3)
    $331.28 each
    Not Added to List Icon Add to List
    Added to List Icon List
    26
    Tue, Nov 2
    26
    QtyArrives
    26 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • #90 Extrol EX-90 Expansion Tank (14 Gallon) Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    #90 Extrol EX-90 Expansion Tank (14 Gallon) 112-1 #90 Extrol EX-90 Expansion Tank (14 Gallon)
    SKU: 112-1 Amtrol
    SKU: 112-1
    Brand: Amtrol
    (15)
    $188.41 each
    Not Added to List Icon Add to List
    Added to List Icon List
    23
    Tue, Nov 2
    23
    QtyArrives
    23 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • 1/2" External NPT<br>Heating Expansion<br>Tank (4.4 Gallon) Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    1/2" External NPT Heating Expansion Tank (4.4 Gallon) TK300-30 1/2" External NPT Heating Expansion Tank (4.4 Gallon)
    SKU: TK300-30 Resideo
    SKU: TK300-30
    Brand: Resideo
    (6)
    $48.79 each
    Not Added to List Icon Add to List
    Added to List Icon List
    109
    Tue, Nov 2
    109
    QtyArrives
    109 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • RX-15 Radiant Extrol Expansion Tank (2 Gallon) Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    RX-15 Radiant Extrol Expansion Tank (2 Gallon) 140-705 RX-15 Radiant Extrol Expansion Tank (2 Gallon)
    SKU: 140-705 Amtrol
    SKU: 140-705
    Brand: Amtrol
    (7)
    $66.93 each
    Not Added to List Icon Add to List
    Added to List Icon List
    48
    Tue, Nov 2
    48
    QtyArrives
    48 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • 1/2" Pro-Pal Full Port Brass Ball Valve w/ Hi-Flow Hose Drain - FIP x FIP (600 WOG) Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    1/2" Pro-Pal Full Port Brass Ball Valve w/ Hi-Flow Hose Drain - FIP x FIP (600 WOG) H-44672 1/2" Pro-Pal Full Port Brass Ball Valve w/ Hi-Flow Hose Drain - FIP x FIP (600 WOG)
    SKU: H-44672 Webstone
    SKU: H-44672
    Brand: Webstone
    (1)
    $26.31 each
    Not Added to List Icon Add to List
    Added to List Icon List
    62
    Tue, Nov 2
    207
    QtyArrives
    62 Tue, Nov 2
    145 Tue, Nov 2 – Wed, Nov 3
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • Fill Control Valve Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    Fill Control Valve 109-15 Fill Control Valve
    SKU: 109-15 Amtrol
    SKU: 109-15
    Brand: Amtrol
    (10)
    $45.00 each
    Not Added to List Icon Add to List
    Added to List Icon List
    21
    Tue, Nov 2
    21
    QtyArrives
    21 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • Expansion Tank Bracket (Full Kit) Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    Expansion Tank Bracket (Full Kit) HN-2 Expansion Tank Bracket (Full Kit)
    SKU: HN-2 Axiom
    SKU: HN-2
    Brand: Axiom
    $71.10 each
    Not Added to List Icon Add to List
    Added to List Icon List
    21
    Tue, Nov 2
    21
    QtyArrives
    21 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
  • SX-90V Extrol Expansion Tank (44 Gallon) Product Image
    Not Added to List Icon Add to List
    Added to List Icon List
    SX-90V Extrol Expansion Tank (44 Gallon) 118-153 SX-90V Extrol Expansion Tank (44 Gallon)
    SKU: 118-153 Amtrol
    SKU: 118-153
    Brand: Amtrol
    (4)
    $658.13 each
    Not Added to List Icon Add to List
    Added to List Icon List
    2
    Tue, Nov 2
    2
    QtyArrives
    2 Tue, Nov 2
    Questions? Call 1-888-757-4774
    Not Added to List Icon Add to List
    Added to List Icon List
FAQs, Manuals & Videos
View Resources

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, and Bell & Gossett expansion tanks to suit all of your plumbing and heating needs.
  • Product Image

  • Product Image

    Select 2 to 3 items to compare

  • Product Image

    Compare up to 1 more item

Why don't we show the price of this item?

We try to always offer you the lowest prices possible, but some manufacturers require that we only show these low prices once you take further action.

To see the price, simply add the item to your cart or sign in.