Weber Silver BBQ has 3 burners only 1 has normal flame.

call Weber, number in your papers that came with item.

This sounds like a reg problem not enough pressure for 3 burners .

Don't worry, you'll be grilling in no time, if you follow these instructions:

1. Turn the gas tank valve OFF.

2. Disconnect the grill's hose from the propane tank and wait 5 minutes.

3. Reconnect the hose to the tank and open the tank's gas valve VERY, VERY SLOWLY (Slow Motion, slow).

Once the valve is fully open light one burner and turn it to HIGH. Has the flame height returned to normal? If so, light the remaining burner and turn it to HIGH. Do both flame heights look normal?
If so, you solve the problem! Remember to always turn the tank valve ON Very, Very Slowly.

Hope this helped you. Please let me know and Happy Grilling!!

Well, I personally, wouldn't want to go from a 3-burner to a 2-burner because I think Weber designed the 3-burner grill to perfection, and as you know, all you have to do is turn off the middle burner.

At any rate, indirect is harder with the two-burner because of the placement of the burners. You can try to put some 1" thick ceramic bricks directly on the flavorizer bars in the middle, or if you are using a rotisserie, put a pan under your meat.

Only front burner lights (out of three) and it only has flame comming out of half of the tube.

It sounds like it needs a good clean!

The new style OPD valves have a small brass ring located in the female fitting on the LP tank. Over time this ring can work loose and then it does not allow the male fitting to fully depress the OPD valve thus reducing your gas flow
Using a small flat bladed screw driver tighten the small brass ring This should solve your problem
IF not you might want to remove the cap (white) on your regulator and try slowly adjusting the regulator, make small adjustments and try the BBQ My Weber if I set the front and back burners to MED I get right at 350 degrees in 60 degree outdoor temps. Adjusting the regulator will take some time to get it right but If it is not your tank it is most likely your regulator out of adjustment

That's fairly common with the lid closed and a day that is not too cool. Keep in mind that a gas flame is about 800F. Try using only one burner on low or between on and high to get a lower temperature. This is a grill, not a smoker or slow cooker.

It will run cooler with a large amount of food.

hi my name is mark, could be one of two things the regulator on the propane tank try gently tapping on regulator it could be sticking, and make sure the vent on regulator does not have a spiders web . or the orifices to the burners are restricted. check regulator some are ajustable, some are not. hope that helps. thanks for your question.

THIS IS YOUR ANSWER RE: LOW HEATING:

http://www.weber.com/support/faq/faq.aspx?id=1