Gas BBQ grill problem
 

We have a BBQ, propane grill that is pretty new, however, it has trouble getting heat.

I can turn on one burner, sometimes two and get decent heat. But If I turn on all four it just dies out. Is it the regulator or the burners?

regulator is set too low. most new ones are not adjustable so you will probably have to buy a new one.

Switch to charcoal.

http://www.biggreenegg.com/index.html

;)

You can try to reset the regulator by turning off the gas, removing the regulator from the the tank, wait about 45 seconds, reinstall and light

Common problem, easy fix. What happens is when you open up that valve on the tank the regulator is hit with a spike of pressure. It pushes back against this and now the regulator is going to flow more slowly than it should.
The fix is to close the tank valve and leave your burner valves open to make sure there is no back pressure in your grill. Then slowly open, actually just barely crack the tank valve again, then open slowly. This will set the regulator for more flow.
I ran into the same problem and actually googled and found this solution and it worked.

Quicksilver, I think you have that backwards.

The regulator will go into emergency mode when it senses too great a draw - which could be happening when all of the burners are on. All burners should be turned off before the tank valve is opened. Once on and at pressure at the regulator, you can then turn on/light your burners.

The regulator may not be rated for the gas flow all of the burners would draw when full - check with the MFG.

Yeah I didn't specify to close your grill valves again and I think the article did. Honestly though, I think the main thing is to open that tank valve correctly and not hit that regulator so hard.