# 420 pound propane tank regulator for generator



## Bulldogger (Feb 19, 2021)

I purchased a used 420 pound/120 gallon propane tank. I have a set-up I purchased from U.S. carb for a 100 pound tank that came with a regulator. The tank has a regulator but it’s much larger than the small red one, 11psi or something that came with kit. What size regulator do I need at tank for this 420 pound tank?






This is what’s on tank now


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## drmerdp (Apr 10, 2018)

Are there any numbers stamped on the tanks regulator?

What regulators did USCarb spec out for you?


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## Bulldogger (Feb 19, 2021)

drmerdp said:


> Are there any numbers stamped on the tanks regulator?
> 
> What regulators did USCarb spec out for you?


Think it’s wrong type on tank. Believe it needs to be red, high pressure first stage. U.S. carb sent I think an 11 or 12 psi. Both they sent didn’t work, bad batch. I purchased an adjustable one locally that adjust from 0-20 psi. Running generator with it at about 12psi. Green one that came with tank I believe is low pressure.


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## iowagold (Jan 22, 2020)

soooo
what all are you going to run off the 120 gallon tank?
you choose the regulator by the btu or the cu ft of flow as well as the pressure.

most lp systems use a two stage or two regulator system then a third demand regulator.
the last (middle regulator) pressure regulator needs to be at the 11-13 wc to feed the demand (safety flow) regulator.

now with that said...
you need to think on the pipe and hose runs size and length!
so if you are running a long run from the tank to the final device, 
run the first stage regulator (higher pressure)
until you get super close to the device then run the 11-13 wc regulator then the demand regulator.
this will help keep the btu available up at a high volume!

also place a full port ball valve at the tank line just after the tan connection.
and another just before the demand regulator!
this will help keep the feed lines full of LP during a tank swap....
or also give you fast shut off for safety at the two locations.


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## Bulldogger (Feb 19, 2021)

iowagold said:


> soooo
> what all are you going to run off the 120 gallon tank?
> you choose the regulator by the btu or the cu ft of flow as well as the pressure.
> 
> ...


 I was using the kit from U.S carb MFI PGK-12 - MFI PGK-12 (Recommended for engines above 20HP) - Motorsnorkel by US Carburetion . I believe I will need a high pressure regulator at my 120 gallon tank? I have a small high pressure one, like in the link but don't think that would work with a larger tank? Well work and be stable long term? Ultimately I plan to have two 120 gallons tanks.

Also, what do you think about the need for a tank blanket, warmer for cold weather, like single digits or in the teens?


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## mtucker (May 9, 2021)

Is this propane tank just for running the generator and as a temporary connection when you need to run the generator? I feed my two small dual fuel generators right off my 250 gallon propane tank. I don't have any additional regulators at the 250 gallon tank. I just use the regulator and demand regulator/shut-off device that came with the generators (attached to the generators). For a given temperature, the pressure in a big propane tank is the same as the pressure in a small 20# propane tank. So your generator and generator regulator doesn't see a difference between a tiny propane tank and a 500 gallon tank. My connection is temporary and I only connect the hose to the unregulated connection on my 250 gallon propane tank when using the generators.
You of course can regulate down right at the tank to something less than tank pressure but greater than the regulator at your generator.


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## iowagold (Jan 22, 2020)

Bulldogger said:


> I was using the kit from U.S carb MFI PGK-12 - MFI PGK-12 (Recommended for engines above 20HP) - Motorsnorkel by US Carburetion . I believe I will need a high pressure regulator at my 120 gallon tank? I have a small high pressure one, like in the link but don't think that would work with a larger tank? Well work and be stable long term? Ultimately I plan to have two 120 gallons tanks.
> 
> Also, what do you think about the need for a tank blanket, warmer for cold weather, like single digits or in the teens?


yea a tank blanket on a thermostat is a great idea!
make sure to have it rated for the tank.
and i would make it as a demand heat system for in use.
yea higher pressure with high pressure LP rated ball valves at both ends.
they also have those safety cut outs if you are in earth quake zone.
they had a 3.0 in the mid west last week!


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## drmerdp (Apr 10, 2018)

Bulldogger said:


> I was using the kit from U.S carb MFI PGK-12 - MFI PGK-12 (Recommended for engines above 20HP) - Motorsnorkel by US Carburetion . I believe I will need a high pressure regulator at my 120 gallon tank? I have a small high pressure one, like in the link but don't think that would work with a larger tank? Well work and be stable long term? Ultimately I plan to have two 120 gallons tanks.
> 
> Also, what do you think about the need for a tank blanket, warmer for cold weather, like single digits or in the teens?


What’s size generator are you connecting this too? Tank blankets are only needed in extreme cold, very large BTU consumption, or a combination of the two.


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## Bulldogger (Feb 19, 2021)

mtucker said:


> Is this propane tank just for running the generator and as a temporary connection when you need to run the generator? I feed my two small dual fuel generators right off my 250 gallon propane tank. I don't have any additional regulators at the 250 gallon tank. I just use the regulator and demand regulator/shut-off device that came with the generators (attached to the generators). For a given temperature, the pressure in a big propane tank is the same as the pressure in a small 20# propane tank. So your generator and generator regulator doesn't see a difference between a tiny propane tank and a 500 gallon tank. My connection is temporary and I only connect the hose to the unregulated connection on my 250 gallon propane tank when using the generators.
> You of course can regulate down right at the tank to something less than tank pressure but greater than the regulator at your generator.


 Thanks. Primary information I needed. My tank will be just for a generator. I have had the small hose end regulators fail. Two I got with my conversion kit did. First one, leaked while I was testing and installing my conversion kit and my whole garage was "full" of propane when I got back home. I don't have much experience with propane but am assuming a the larger permanent mount tank regulator would be a bit more robust. This tank will be about 75 feet from my house but still don't want any leaks.


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## drmerdp (Apr 10, 2018)

You should be using a red high pressure regulator at the tanks, then your 75ft run, then a green low pressure regulator near the generator to feed the demand regulator on the generator.


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## Bulldogger (Feb 19, 2021)

drmerdp said:


> You should be using a red high pressure regulator at the tanks, then your 75ft run, then a green low pressure regulator near the generator to feed the demand regulator on the generator.


 Right, well partly. Right as I replied earlier, red regulator is high pressure. No, the 75 feet will be covered by generator cord. A 75 foot propane line? Naw, that's going to invite more temperature problems in very cold weather unless it was buried? That's more work! Propane line right now is 12 feet.


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## drmerdp (Apr 10, 2018)

Bulldogger said:


> Right, well partly. Right as I replied earlier, red regulator is high pressure. No, the 75 feet will be covered by generator cord. A 75 foot propane line? Naw, that's going to invite more temperature problems in very cold weather unless it was buried? That's more work! Propane line right now is 12 feet.


Ah-ha, I miss understood. Yeah that changes things quite a bit.


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## Bulldogger (Feb 19, 2021)

drmerdp said:


> What’s size generator are you connecting this too? Tank blankets are only needed in extreme cold, very large BTU consumption, or a combination of the two.


 I am using the Powerhorse 99932, which uses 2.15 GPH of gasoline at half load so I'd figure a bit more on propane? That generator at full load could drain that tank in one day, assuming a linear consumption rate, faster if it's not linear. A repeat of last years ice storm and with that rate of consumption, the likelihood of a temperature related severe pressure drop seems certain.


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## iowagold (Jan 22, 2020)

yea get the blankets...
you do not have to use them till it gets super cold out.
and warm hoses and regulators are nice as well...
maybe a gen shack?


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