Propane BTU's ?

[PP]

I've been purchasing some very inexpensive (cheap  ) propane for the last few fills and I can't help but wonder if it doesn't burn as hot as what I've used in the past. Even the wife says her french fries are boiling rather than frying because the oil isn't getting hot enough. Makes for soggy fries. I told her it's because we're at a higher altitude  (which is true) because we've been parked at almost 5000' for a while now taking in the winter activities (hibernating). Things boil at lower temps the higher you go. So, is this possible that the propane is lower grade or is it my imagination? It's .94/gal vs 1.99 to 2.49/gal everywhere else.
Thanks in advance, Will

[sledhead]

this might help ?

http://juxtamorph.com/butane-versus-propane-which-is-hotter/

dave

[luvrbus]

It will be same btu only problem the oil will build up in the burners and orifice on stoves and burners I need to clean mine about every 5 years or so because of it, my BBQ grill has to be cleaned about every 2 years fwiw ( I pay $.99 a gal too)  

[Lin]

We had a problem with the oven and stove not really putting out as much heat as they should have.  It turned out the somehow the pressure regulator had gotten way out of adjustment.  A little increase in pressure gave us out flame back.

[PP]

Wow, thanks for the quick answers everyone. I think we all know why Cliff's barby needs more frequent cleaning than his bus hobs  I hadn't even considered the regulator differences until I read the link from Sledhed. So I tried an experiment. I switched from the auxiliary tank to the main tank and what a difference. Instead of taking 6 minutes to heat a kettle of tea, it now only takes a little over 3. Different regulators. The regulator on the main tank has an adjustment knob on it, but the one on the auxiliary doesn't-it's the same as you find on a barby. That doesn't mean it can't be adjusted, I just haven't found the right hammer yet    If it's a simple thing to do, can someone please shed that light my way? (Ball peen, roofing, framing?)
Again, thanks everyone for your responses. (Note- I included the bus to keep this in the right area  )