>I couldn't get the grill to more than 350 degrees. Obviously something
>isn't right. The Webber manual says that you should disconnect the
>regulator and open the burners for 1 minute, reattached and that should
>fix it. I tried that with no luck.

From the Weber site:

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Also from the Weber site:

Q. My LP gas grill won't get hotter than 250 to 300 F, even with all
burners on high. Why?

Since 1995, all regulators (the part that attaches to the gas tank to
regulate the flow of gas) have included a safety device that restricts
the gas flow in the event of a gas leak. But, you can inadvertently
activate the safety device without having a gas leak. This typically
occurs if you open the LP tank valve rapidly, or if one or more of the
burner control knobs is in an open position when opening the LP tank
valve. If you do activate the gas regulator safety device, the grill
will only reach temperatures between 250 and 300F even with all
burners on the high setting. To reset the gas regulator safety device:

* Close the LP tank valve.
* Turn all burner control knobs to the OFF position.
* Disconnect the regulator from the LP tank.
* Open the lid of the grill.
* Turn burner control knobs to HIGH.
* Wait at least 1 minute.
* Turn burner control knobs OFF.
* Wait at least five minutes if the barbecue has been lit.
* Re-connect the regulator to the LP tank.
* SLOWLY turn the LP tank valve all the way open.
* With the lid open, turn the front burner control knob to the
HIGH position (for Summit gas grills, turn on the left burner in
the selected Heat Zone).
* Ignite the grill by pushing the crossover ignition button
several times.
* After the front burner is lit, turn the middle burner control
knob (if your barbecue has three burners) and then the rear
burner control knob to the HIGH position. (For Summit gas
grills, turn on the right burner)
* Close the barbecue lid.
* The barbecue should reach 500 to 550 degrees in 10 - 15 minutes.