Lets discuss a couple of possibilities... 1) When you are holding the regulator, and regulator is attached to the fitting that screws into the bulk tank, the burner is able to fire. But, if you let go, burner goes out.
Likely that the Excess Flow Valve is damaged / not assembled correctly. You may be able to buy a pig tail propane connector and replace the connector if the connections are threaded. Most are crimped though.
2) When you hold the regulator in your hand, in particularly covering up a discharge vent / equalization port on the regulator, propane is now able to flow where it needs to go.
Then the regulator likely has a damaged diaphragm in it. Easily replaced with aftermarket regular for such appliances that are available at retail stores, as well as specialty stores geared towards recreational vehicles.
3) This one is a bit harder to diagnose... If the ambient temperature is cold already, and holding the regulator allows burner to light, letting go of the regulator should result in the burner flame getting smaller until it goes out. It may also shutoff very quickly if temperature is very cold.
Your bulk tank / propane supply has been contaminated with moisture. Moisture has accumulated inside the regulator, and the expanding propane liquid to propane gas is freezing the moisture, cutting off propane flow. This is actually quite common. To further test this, take a towel, soak in hot water, wrap around the regulator (don't block vents though). If burner continues to burn normally, you have a moisture problem. Either your cylinder (20#?) has moisture in it, or the regulator assy has been allowed to get wet. Either way, plan on replacing the regulator (I would do lines as well). Replacements are available from Large Blue Retail Stores as well as specialized stores for recreational vehicle worlds.
Answers & Comments
Lets discuss a couple of possibilities...
1) When you are holding the regulator, and regulator is attached to the fitting that screws into the bulk tank, the burner is able to fire. But, if you let go, burner goes out.
Likely that the Excess Flow Valve is damaged / not assembled correctly. You may be able to buy a pig tail propane connector and replace the connector if the connections are threaded. Most are crimped though.
2) When you hold the regulator in your hand, in particularly covering up a discharge vent / equalization port on the regulator, propane is now able to flow where it needs to go.
Then the regulator likely has a damaged diaphragm in it. Easily replaced with aftermarket regular for such appliances that are available at retail stores, as well as specialty stores geared towards recreational vehicles.
3) This one is a bit harder to diagnose... If the ambient temperature is cold already, and holding the regulator allows burner to light, letting go of the regulator should result in the burner flame getting smaller until it goes out. It may also shutoff very quickly if temperature is very cold.
Your bulk tank / propane supply has been contaminated with moisture. Moisture has accumulated inside the regulator, and the expanding propane liquid to propane gas is freezing the moisture, cutting off propane flow. This is actually quite common. To further test this, take a towel, soak in hot water, wrap around the regulator (don't block vents though). If burner continues to burn normally, you have a moisture problem. Either your cylinder (20#?) has moisture in it, or the regulator assy has been allowed to get wet. Either way, plan on replacing the regulator (I would do lines as well). Replacements are available from Large Blue Retail Stores as well as specialized stores for recreational vehicle worlds.