Rob,
I read your post and I am not in agreement with the steps you listed.
I know the OP is using the small cylinder and you and I are using a hose attached to a refillable cylinder.
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> 3) After the 5 minutes, turn off the temp control, and re-attach the hose to the Q and then the tank. Make sure that the temp control is in the on position.
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I do not know why this step states to make sure the temp control is in the ON position!
This procedure seems like it is from the early excess flow fitting time when they didn't reset automatically.
1st of all when turning on the tank valve w/hose before the regulator there is a flow control fitting (excess flow valve ) incorporated in the PLO fitting and if the hose between this fitting and the pressure regulator/control valve is at very low pressure and the the fuel will flow rapidly into hose and in doing that the excess flow valve will trip because more vapor than the BTU value of the PLO is seen. If your control valve is in the OFF position and you do not turn on the control valve right away you will probably never know this safety flow control valve tripper because it will automatically reset in a short time, probably between 1/2 and 3 min.
If you are observant, and have good hearing you will be able to hear this fitting trip, and reset if there are no leaks and the grill control valve is in the off position.
Mos grills set up with regulators that are at the cylinder connection will not have a problem with the excess flow valve at any time because the regulator when functioning properly will not over flow the BTU limit of the PLO fitting unless there is a regulator free flow.
Ads for the OP's problem, I have only used a disposable cylinder one time and that was the 1st time I used my 1st Q and had the wrong cylinder at the time and had to remove the bracket for the skinny disposable. My 2nd Q is ready for the husky one.
I do not know of any flow sensor functions in the control valve and disposable cylinders do not have any, so all I can think of is maybe a cylinder that isn't fully connected, maybe?
OR, I have had trouble when the drip pan was full of water.
If you figure out your problem please post what you found.