Whether or not you have a detector, it is good practice to test your propane system periodically. This is how you do it. Both tests are necessary for a safe system.

With the stove off turn the valve at the tank on, and turn the solenoid on. Note the gauge pressure- you do have a gauge, right. Turn the valve at the tank off, leave the solenoid valve on and watch the gauge for 15 minutes. If the pressure hasn't changed, then there is no leak in the lines.

There is a second test which will establish whether the solenoid valve is working. Turn the valve at the tank on and the solenoid valve. Light the stove. Turn the solenoid off. The burner should go off in a few seconds.

I believe that if you do these tests every three months or so and rigorously use the solenoid valve then your propane system will be safe.

David