Note that the water enters from the left in this photo (side with union),
and goes up to the EBB FLOW Bench through the hose on the right. After
the bench is done filling, the water returns through the same hose, and
drains through the bottom of the "T" fitting into the gravity
drain line.
Note that the drain from the GROmaster valve into the drain line is open
to the air.
This is important - the valve will not operate correctly if this is not
an open connection.
Shown below, is a typical installation of the GROmaster valve.
On the right is the water supply line (pressurized supply from pump at main holding tank.)
When your controller applies power to the solenoid valve, it open, and water flows through the MIDWEST GROmaster valve, and the hose up to the EBB-FLOW Bench
When the solenoid valve is turned off, the water drains back from the bench, through the hose, and the MIDWEST GROmaster valve, into the drain line, to return to the holding tank.
Shown above is an overall view of a typical installation of the MIDWEST GROmaster bench valve under an EBB-FLOW bench.
The main drain and fill lines, along with the solenoid valve and GROmaster valve assemblies should located approximately 4 feet back from the end of the EBB-FLO® bench at the end where the plumbing connections will be made.
It is very important that the hose connecting the GROmaster valve to the bench not be too short. It must hang loosely, so as to not put strain on the connection to the EBB-FLOW bench. This is especially important if you have rolling benches. (Better to have the hose too long than too short!)
The connection to the EBB-FLOW bench is made with a fitting provided through a hole in the plumbing well of the EBB-FLOW tray. The fitting should be hand tight, and made with the rubber gasket on top of the bench. The hole for the fitting is made with a 1-5/16" hole saw. The screen provided is inserted in the top of the connection fitting, and the bench filter (stainless steel screen) is placed over the plumbing well.
The fill (pressurized) line can be 1", 1 ½", or 2" PVC pipe depending on the size of your installation. (Most typically this is 1 ½" pipe.)
The gravity drain line is typically 3" or 4" PVC pipe. The stub under each bench into which the GROmaster valve drains is typically 2" PVC.
The solenoid valve, and the GROmaster valve are all 1" pipe. The
union shown in the pictures is not required, but is recommended for ease
in future repairs. NOTE: If your greenhouse is not heated all winter, and
may freeze, you may want to locate the union on the inlet side of the solenoid
valve. This will allow you to easily disconnect the plumbing, and drain
the system before freezing weather.
This is another view of a typical GROmaster bench valve installation.
NOTE: Water line and drain line in this example are about 12" apart. This distance can vary, but the combination of fittings in the assembly from the water line through the solenoid valve and GROmaster valve must result in the GROmaster valve being aligned with the stub up from the drain line
Union shown is optional, but recommended. It could be on either side of the solenoid valve.
