Auto fill component test

Fresh off of another good brew, I decided it was time to begin work on the control panel and components again. I had just received a few components from McMaster-Carr that enabled me to move forward with tank holes for the new additions. To start I decided to test and prepare for the auto water fill and shutoff for the HLT.

Parts

The parts that I received that enable me to do this include the following:

• 1/2" Stainless Plugs: in case I need to seal off any holes without the intended device in place
• High Temp O-rings: used on both sides of the tank to seal the hole
• 1/2" Stainless Lock-Nuts: tightening over the thread inserted into hole in tank

Assembly

First step: was drilling the hole into the side of the tank. This consisted of finding the high part on the tank side with no curve and drilling a 7/8" hole. This is relatively easy with a metal hole saw, assuming you go real slow.

Second step: was inserting the float switch, aligning it correctly (normally closed), and sealing it off by using two O-Rings and a lock-nut on the inside. The outside of the float switch also has a 1/2" thread which will be helpful. My intent is to permanently affix a coupler to the back half of the float switch thread, connect the leads to a female port that sits inside the coupler and affix the inside coupler with glue. This will enable me to remove the leads for cleaning.

I continued by affixing the wires from the float switch to the back of the control panel at the appropriate spots.

Third step: was connecting one side of the solenoid to the hose and the other to the HLT tank. The solenoid is normally closed, but interestingly some water did get through until full water pressure was applied from the hose. I then connected the solenoid to the appropriate ports on the back of the control panel

The test: so the idea behind this whole thing is to have push button water flow, in addition to auto water shutoff for the HLT. If you look at the control panel you will see a push button at the top. This is a momentary button and is used to open or close the solenoid. What is happening is the button is connected to a triggered relay that toggles its state on or off when it is pulsed. Thus, every time I press the button the relay gets pulse and 24 volts are sent to the solenoid to open it. When the button is pressed again the relay is triggered closed, cutting of power to the solenoid, thus closing it. The float switch works the same way essentially. When the float piece is down and the tank is low the connection in the circuit is closed, but when the water raises the floating piece level the connection is made. Thus, when the button is pressed the first time the HLT will start filling, but once the float switch circuit opens it will trigger the relay to close. The result is of course that the water stops flowing.