On some gas grills, it's impossible to hold the heat down to the desirable smoking range of 200° to 225°. In that case, smoke on the lowest heat level you can maintain, and reduce the cooking time called for in the recipes. You won't get as much smokiness, but you'll still get a good sense of the scent.
1. Soak wood chips for 30 minutes; drain. Many newer gas grills include a smoker box nestled near one of the burners. Added to the box, soaked wood chips will smolder from the heat of the nearest burner. If your gas grill doesn't have a built-in box, make a foil pouch to hold the wood. Place the wood on a piece of heavy-duty foil, and fold up and close loosely.
(A) Pierce the foil about a half-dozen times with a fork to allow smoke to escape.
2. Turn on the burner at the end of the grill nearest the smoker box. (B) If you're using a foil pouch, turn on the burner at one end of the grill, and arrange the pouch very near that burner. If your grill is longer than 36 inches, you may need to turn on two burners to get the proper heat.
3. Place a disposable aluminum foil pan filled with water on the unheated side of the grill. Place the grill rack on the grill. Arrange food on the grill rack directly above the pan on the unheated side of the grill.
4. (C) If your gas grill has no thermometer in its lid, place an oven thermometer on the cooking grate near the food. Adjust the grill knobs as needed to maintain the desired temperature.
5. If you see no more smoke escaping from the grill, add more soaked wood chips to the smoker box or carefully toss on another foil pouch. If you're smoking one large piece of food, rotate it when you have the grill open, but avoid raising the lid more than necessary.