Bansil - you're evil. You know that you are. The Man-O-Meter you're thinking of is called a ruler
Originally Posted by ol trunt
Roach, your cabinets are awsome--the fit and finish is perfect.
Your manometer obviously will work just fine and is quite clever-- it doesn't need it to work but a drop of food coloring would make it easier to read I think. How about 'splaning how a monometer works to the rest of us? Jack
Jack - Me thinks you probably know way better how to use this thing than I do, but here goes.
Propane bottles have pressures varying between not much when empty to around 250 psi when full, but propane appliances require steady pressure of about .5 psi. The regulator sits between the bottles and the appliances and knocks the pressure down so the appliances will be happy. Several things can screw up that pressure adjustment. Sometimes the regulator will get out of adjustment, propane lines can leak or get crimped and sometimes junk gets in the propane tanks and clogs orfices.
So you may have an appliance that's screwing up but how do you know whether it's mechanical or gas pressure related? That's where the manometer comes in. Basically, it's just a clear tube with a little water in it attached to a backer board with a scale which lets you measure pressure in inches of water column. You hook it up to the low-pressure side of the regulator and when you turn on the gas the pressure moves the water column. Typically, propane static pressure (that is, with no leaks or gas appliances running) will be 14 inches of water column. With several appliances running you want to see at least 10 inches.
I built mine out of some foam board and some 1/2" plastic tubing that was laying around, and Instead of using expensive brass fittings to connect to the gas lines I just used electrical tape. The pressure is so low in the propane lines that the tape seals just fine. To test gas pressure to the water heater I disconnected the gas line coming into the water heater regulator and taped the manometer tube to the fitting on the incoming gas line.
You can also use your manometer to test for leaks in the system by pressurizing the system then turning off the propane bottle valves and watching the manometer for any drop in the water column.
Here's a link to instructions for building one:
One mistake I made was to make the lower loop too small and the small amount of water was being blown right out the top of the tube (Bansil,just keep it to yourself
). After much head scratching I finally just made the lower loop longer and that solved the problem.
I built mine because the spider webs in my burner tube made it look like I had very low gas pressure to the heater. By hooking up the manometer I could rule out low line gas pressure.