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Here are the basics of the conversion process:
Make sure the gas is turned off and the dryer is unplugged from the power source.The first thing that you will need to do is purchase a gas dryer
conversion kit. Extreme care needs to be taken when installing the kit and making the conversion, since there is a very obvious safety issue if the kit is not installed properly. The kit will consist of a brass fitting with a nylon pin sticking out of it. This is called the blocking pin. At the gas valve and regulator you will remove the plug on the gas valve (called a leak limiter) and replace it with the fitting containing the blocking pin that comes in the conversion kit. That will change the gas regulator pressure setting from gas to propane.
Next, you will have to change the orifice metering plug in
the burner. This does just what the name implies... it meters the amount of gas that enters the combustion area. The fittings that come with the conversion kit (blocking pin and orifice metering plug) are made of brass, which is a soft metal, and since they are being connected to a much harder steel, make sure that the fittings are not overtightened. I generally use some pipe dope on the threads. Once the conversion is completed, you want to check for leaks. I generally mix up some soapy water and spray it around the fittings to check for leaks. Look for bubbling which is a sign that there is a leak. The last thing to do is to reassemble the dryer. Start it up and make sure that it is operating correctly and that there are no obvious smells that would indicate a leak. If so, shut down immediately.
These are the basic steps for a gas/LP conversion. If there is any doubt that you feel comfortable making the conversion, then I recommend that you contact an appliance technician for assistance. Hope this helped and best wishes.