Titus- I appreciate your input. I will check out your standard. The older LP systems (high pressure Zenith types) were very forgiving of whatever slop you fed them. The lower pressure Impco became more sensitive & their life became much shorter if just any old LP was fed them. I find these new, fuel injected LP systems demand HD-5 grade LP for any kind of life span. I've had these newer systems clog in less than a week with the slop of old.

Educating my customers in the different grades of propane is difficult, as local suppliers don't know/care about anything but pushing product. They are viewed as the "expert" in their field & I'm accused of passing the buck for blaming the fuel for repeated fuel problems.

I wind up letting them use their LP after a fuel service, then disassembling their regulator after about a month to show the "tar". I then clean the regulator, supply them with known good HD-5 LP, & then disassemble their regulator again in a month to show the difference. The look on their face is- as they say- priceless.