Read the manual for the Preway Type E B128B, B136B and B142B fireplaces at Manualslib.com. The manual includes instructions and recommendations for installation, along with chimney case requirements, instructions for installing an outdoor air kit and information on optional equipment. A general set of instructions for Preway fireplaces is available at eHow.com.
Before you light a Preway gas fireplace, stop and check for the smell of gas fumes. Check that the gas valve near the home's gas meter is set to "On," and open the access panel that is on the front of the fireplace. Find the smallest tube that is exiting the main gas pipe; this is the pilot tube. Turn the tube's control knob to "Off."
Wait for several minutes so that any gas remaining in the line has time to escape. If you smell a gas leak at this point, contact the local gas company. If there is no leak, turn the control knob to "Pilot," and hold the knob down. Use a lighter to ignite the gas at the end of the tube. The pilot light needs time to stabilize, so continue holding down the control knob for around 30 seconds. Release the knob, and turn it to "On," and close the control panel. Use the fireplace's main power switch to light the fire.