L-P gas light problem?

[mnhunter2]

I have 2 LP gas lights and a 15000btu empire heater running off a 20# cylinder fubber hose for 4' then a 3/8 line for the lights and a 1/2 line for the furnace. Everything worked fine the first trip but now I can't seem to get the lights to work very well, the mantles seem to only burn part way and seems to pulse like I am not getting enough gas. I took everything apart last night a blew out the lines and orifices with compressed air, got some grey flakey dust out of the lines and it still works poorly only thing I haven't changed is the mantles , the gas man checked my regulator with a pressure guageand said it was fine. Any ideas?

[Jeremy airjer W]

does the hose attatch to the tank with the external threads (acme) or the internal threads.

If it has the acme connector it may be an issue with the EFD (excessive flow device). With everything hooked up and with the lights and heater turned off, open the valve on the tank. you should hear a rush off propane filling the lines/hoses. If this noise stops suddenly the EFD has tripped. Close the valve. wait 30 to 60 seconds (sometimes an audible click can be heard) then open the valve again. Continuem this until the lines are "purged" or brought up to pressure.

Is there a possibility it was just really cold and the evaporation from a liquid to a gas couldn't keep up with your demand?

[End of the Line]

If its cold outside a 20# tank may not have enough pressure to sustain what the system is demanding. This is especially true when the smaller tanks like 20#'s get down below 1/3 full and/or the colder it gets outside. I am guessing the first time you used it the tank was full. Even a smaller house will generally burn at least 6-8lbs per day in LP. If the mantles worked before fine its probably not them. Try using a new or larger LP source. Could be something else too, might need more info on size of house and furnace.

[mnhunter2]

The fishouse is 6.5x14 and has a new 15000btu empire furnace the hose conection is of the type that screws inside the valve on the tank and I was still having trouble when the temp was 25 and a half full 20#tank.

[fivebucks]

As end of the line mentioned, it could be the small 20# lp tank. I have a garage heater that will run on a 20# only when it is full down to 2/3 full and then the output drops to 1/3 of what it was, even when the garage was warmed up. I went to a 40# tank and it works great all the time. Some heaters are only meant to run on bigger tanks. If you have a 40 or 100 avail. to test it, hook it up and I bet it works fine. If anything else it's worth trying just to elimate a potential problem. Good luck.

[Surface Tension]

I also think your tank is too small for the demand. Get a bigger tank or add a second tank to the system.

Using a tank thats too small can get dangerous for guys using the ventless type heaters. Those heaters are designed to burn clean but they can't if the lbs drop beyond their safe operating range. You'll see they recommend 100 lb tanks.

[nitroant]

Where the tanks brand new this year before you hooked everything up? If so your tanks may not have been purged all the way and your getting air and LP through the lines and that will sometimes be the problem.

[Jeremy airjer W]

Except propane is heavier than air. If any air was in the tank the problem should have showed up earlier. I'd have to agree with the others, too much demand not enough supply.