Take control of your hardware with relays.  Solid State relays are recommended for high amperage applications such as elements where as SPDT are recommended for low amp projects such as pumps and valves.  A solid state relay will have a common trait known as leak current.  This current is nominal but can have a negative impact with low amperage projects; for example, the leak current can cause your gas valve to hang open after the intended time frame.  An SPDT relay is similar to a contactor in that it makes a physical connection, and as such you will here a coil click when you send it the signal.  The SPDT relays require a 12 volt power supply in order to operate, but one 15w supply is good for up to 8 relays.

$12.00
40a Solid State Relay. Use in conjunction with a low voltage (6, 12v, 24v) conroller such as BCS, Brewtroller, or PIDs to turn on/off high voltage circuits. New style 40a Solid State Relay. Use in conjunction with a low voltage (6, 12v, 24v)...
$29.00
Avoid the leak current of SSRs when working with valves or other low voltage projects. This board requires a 12v power supply to operate, but takes control signals from the BCS or BrewPi. Providing an effective relay foot print for 2 valves in the space...
$33.00
Avoid the leak current of SSRs when working with valves or other low voltage projects. This board requires a 12v power supply to operate, but takes control signals from the BCS or BrewPi. Providing an effective relay foot print for 4 valves in the space...
$35.00
Avoid the leak current of SSRs when working with valves or other low voltage projects. This board requires a 12v power supply to operate, but takes control signals from the BCS or BrewPi. Providing an effective relay foot print for 4 valves in the space...
$3.50
Heatsink, to use with 40a or less Solid State relay. Install to dissipate the heat produced by high current circuits. This has a channel it it that will attach to the DIN rail. While I use these myself on a DIN rail, it is recommended that you have a...
$35.00
Small tapped aluminum heatsink for external mounting in applications using 1 Solid state relay.Small external heat sink. This heat sink is recommended for those who plan to build 220v electric breweries. Heat sink comes drilled and tapped with mounting...