Sniff all around the Peerless heater to see if you detect the odor of gas. Smell the floor area around the heater as well. If there is a gas leak, the gas may settle there, since gas is heavier than air. If you smell gas, leave the building immediately and call your gas company for assistance and repair. Do not attempt to light the Peerless heater if you smell gas.
Set the thermostat on the Peerless heater to its lowest temperature. Turn off electrical power to the heater.
Look for the gas control assembly. If it is not visible, you will need to remove the control access panel.
Turn the manual shutoff knob to the "Off" position, and then wait five minutes for any gas to clear the heater. Smell for gas again. If you smell gas, leave the building and call your gas supplier right away.
Remove the pilot access panel if your heater has one. The pilot access panel is located below and behind the gas valve, just above the burner tubes.
Follow the thermocouple from the thermopilot valve to find the standing pilot. Turn the pilot cock and the manual shutoff knob to the "On" position. Turn on electric power to the heater.
Push the red reset button on the right hand pilot. Press it all the way in and hold it, then immediately light the right hand pilot with a match. Hold the reset button in for one minute after the pilot is lit. Release the button and let it pop back out.
Replace the pilot access panel you removed earlier. Set the thermostat to the desired setting.
Sniff all around the Peerless heater before you proceed. If you smell gas, leave the area immediately and call the gas company to report a leak. Do not use a telephone inside your home. Go outside and use a cell phone, or ask a neighbor to call the gas company for you.
Set the thermostat on the Peerless heater to its lowest setting. Turn off the electrical power to the heater.
Remove the control access panel if the gas control assembly is not visible. Turn the manual shutoff lever and pilot cock to the "Off" position. Wait five minutes and smell for gas again. Do not proceed if you smell gas. Instead, go outside and call the gas company for assistance.
Turn the pilot cock and manual shutoff levers to the "On" position. Replace the pilot access panel.
Replace the control access panel and turn on the electrical power to the appliance. Manually reset the burner primary control and open limits, then set the thermostat to the desired setting.