Regulators and How They Work
by Marc WardClay Times Oct 1999
Inspiration comes from odd places. I'd been racking my brain to come up with a topic for this month's column when the subject forced itself on me.
I've just hung up the phone trying to track down my order of long, lost regulators. They're in customs, they're at port, they're on a truck....they ain't here where I need 'em. So while I wait, I'll tell ya'll about regulators. I get to write the word "ya'll" cause I'm from the South. Our new columnist, Tony Clennell gets to end most of his sentences with "eh" because of the Canada thing. (Tony, I owe you that one for the comment about techno-wienies in one of your past articles in another magazine :-).....welcome aboard!)
So, regulators it is. A regulator does one thing and one thing only. It reduces a higher pressure coming into the regulator to a lower pressure coming out of it. You can't put a10 PSI (pounds per sq. inch) regulator on a line that has low pressure (like 11 inches water column which is about .333 PSI) and get a higher pressure. It only works in one direction. Higher pressure to lower pressure. And, it only works in one direction so make sure the gas is moving through the regulator in the direction of the arrows on the body. If there are no arrows, make sure the inlet and outlet are piped correctly.
A regulator works by having two chambers. The upper chamber feeds the lower pressure output (downstream) and the lower chamber is feed by the input (upstream) higher pressure. Between these two chambers is a diaphragm that seals between them. A spring in the top chamber holds this diaphragm down and seals off the bottom (inlet) chamber. Connected to this diaphragm on the bottom side is a lever that closes off the inlet orifice. When the pressure inside the bottom chamber gets great enough to overcome the pressure of the spring, it lets gas into the upper chamber and out to the burners. When this diaphragm rises to let in gas, it pulls on the lever and closes off the inlet. This action reaches a balance causing the inlet pressure to be reduced (regulated) to a certain amount at the outlet. The strength or compression of the spring determines how much force is needed to raise the diaphragm. The stronger the spring, the higher the outlet pressure. Or in the case of adjustable regulators, the more you crank down on the adjustment, the more compressed the spring is and, therefore, harder to raise. This means a higher outlet pressure. OK,....I know that's hard to follow, but believe me, that's what happens.
With propane, the gas company will provide you with regulator(s) to give you the pressure you need. In almost all cases (except weed burners...and the name says what I think they're for) you've got to have a regulator on a propane tank. A propane tank may have 200 PSI in it. The pressure drops as you use up the fuel. This is like driving your car without brakes or an gas pedal. When the tank is full, you go 120 miles an hour and as your gas runs out you slowly start to lose speed. It's no way to drive or run burners. As for natural gas, the meter is also a regulator that reduces street or feed pressure down to what they give you. Unlike propane, you may not have much of a choice about what that pressure is.
Regulators need to be kept out of the weather. They are enclosed in your natural gas meter. They live under that little dome on your propane tank or they hide under your roof overhang on the wall like some mechanical, fossilized turtle. All this is for a reason. If moisture gets inside them through their vents. The springs can freeze during cold weather and cause the regulator to lock-up. Bad, bad, bad. Treat regulators with some respect and protect them from the rain, snow, and dirt. Another consideration with some regulators is positioning. You may not be able to place them upside down or vertically. If unsure, check with the folks that supplied the regulator. One last word, industry standards specify that propane regulators have a fifteen year life span. They can last longer or die before their time. If you're unsure or having problems, call your propane supplier. As far as natural gas, it's a public utility and they're out there checking on things on a regular basis whether you're aware of it or not.
Inspiration comes from odd places. I'd been racking my brain to come up with a topic for this month's column when the subject forced itself on me.
I've just hung up the phone trying to track down my order of long, lost regulators. They're in customs, they're at port, they're on a truck....they ain't here where I need 'em. So while I wait, I'll tell ya'll about regulators. I get to write the word "ya'll" cause I'm from the South. Our new columnist, Tony Clennell gets to end most of his sentences with "eh" because of the Canada thing. (Tony, I owe you that one for the comment about techno-wienies in one of your past articles in another magazine :-).....welcome aboard!)
So, regulators it is. A regulator does one thing and one thing only. It reduces a higher pressure coming into the regulator to a lower pressure coming out of it. You can't put a10 PSI (pounds per sq. inch) regulator on a line that has low pressure (like 11 inches water column which is about .333 PSI) and get a higher pressure. It only works in one direction. Higher pressure to lower pressure. And, it only works in one direction so make sure the gas is moving through the regulator in the direction of the arrows on the body. If there are no arrows, make sure the inlet and outlet are piped correctly.
A regulator works by having two chambers. The upper chamber feeds the lower pressure output (downstream) and the lower chamber is feed by the input (upstream) higher pressure. Between these two chambers is a diaphragm that seals between them. A spring in the top chamber holds this diaphragm down and seals off the bottom (inlet) chamber. Connected to this diaphragm on the bottom side is a lever that closes off the inlet orifice. When the pressure inside the bottom chamber gets great enough to overcome the pressure of the spring, it lets gas into the upper chamber and out to the burners. When this diaphragm rises to let in gas, it pulls on the lever and closes off the inlet. This action reaches a balance causing the inlet pressure to be reduced (regulated) to a certain amount at the outlet. The strength or compression of the spring determines how much force is needed to raise the diaphragm. The stronger the spring, the higher the outlet pressure. Or in the case of adjustable regulators, the more you crank down on the adjustment, the more compressed the spring is and, therefore, harder to raise. This means a higher outlet pressure. OK,....I know that's hard to follow, but believe me, that's what happens.
With propane, the gas company will provide you with regulator(s) to give you the pressure you need. In almost all cases (except weed burners...and the name says what I think they're for) you've got to have a regulator on a propane tank. A propane tank may have 200 PSI in it. The pressure drops as you use up the fuel. This is like driving your car without brakes or an gas pedal. When the tank is full, you go 120 miles an hour and as your gas runs out you slowly start to lose speed. It's no way to drive or run burners. As for natural gas, the meter is also a regulator that reduces street or feed pressure down to what they give you. Unlike propane, you may not have much of a choice about what that pressure is.
Regulators need to be kept out of the weather. They are enclosed in your natural gas meter. They live under that little dome on your propane tank or they hide under your roof overhang on the wall like some mechanical, fossilized turtle. All this is for a reason. If moisture gets inside them through their vents. The springs can freeze during cold weather and cause the regulator to lock-up. Bad, bad, bad. Treat regulators with some respect and protect them from the rain, snow, and dirt. Another consideration with some regulators is positioning. You may not be able to place them upside down or vertically. If unsure, check with the folks that supplied the regulator. One last word, industry standards specify that propane regulators have a fifteen year life span. They can last longer or die before their time. If you're unsure or having problems, call your propane supplier. As far as natural gas, it's a public utility and they're out there checking on things on a regular basis whether you're aware of it or not.