It’s very important that there are people with your skills, as some folks are not equipt or comfortable to take on a project like this.

I would think the orifices are specific for each appliance (BTU ratings). As an example, our kitchen stove has 4 different sized burners and each one appeared to have different sized orifices. I would definitely recommend contacting the manufacturer for the correct size. If the orifice is too small it could underperform. If it’s too large, it could be a fire hazard. Please use extreme care.

Let me start by saying I am not an appliance service technician. So I am not familiar with the screw inside of the gas valve. You may need to contact the manufacturer to get that information. I can tell you that you definitely need a regulator between the propane tank and any appliance. Typically right outside the house. Propane appliances operate on only about .4 psi, which is about 11″ of water column (wc). I would start there. Propane is very flammable/explosive, so I would not try operating the dryer again until a regulator is installed.

I’m glad it helped!

Do not use it unless you are sure it came fitted with the orifice for propane! Propane has more BTU’s (British heating units) than natural gas and is therefore much more flammable than natural gas, so the propane orifice is smaller. If you use the larger natural gas orifice with propane, the flame will be much larger and hotter than it should be and could be a fire hazard. Verify with the store you purchased the dryer from what orifice came installed. They should be able to tell you.