It was about 85° with a 15-knot wind (or so) when I set-up my PG500 for smoking jerky at 180°.  The LHt was initially 20 for the pre-heat.  The temperature stayed extremely low so I threw a handful of pellets into the burn pot to drive it up and heat the metal.  It went up well over my 180° target and I let it settle down.  Unfortunately it fell quite a bit below 180°.

I raised the LHt to 25 and watched it improve, but not enough.

LHT of 30 appeared to be the answer so I loaded the jerky and left the house, asking Marcia to look out periodically to see if it was continually smoking (I was worried about flame-out).  I was gone for a while confident that the arrangement was safe, since the pit was on a patio well away from flammables.

A few hours later the temperature graph showed that the pit never went to HHt mode while I was gone.  The temperature had cycled between 125° and 155°.  Marcia said that there were times when the pit made a lot of smoke but that she never saw white smoke.  The low temperatures kinda delayed the jerky cook completion.

These low temperatures were new to me and I don't know what to attribute them to.  The pit was clean and the CookinPellets Perfect Mix had just been opened for this smoke.

I don't view it as a problem, I'm just curious.  What are your thoughts?  Wind?  Low pellet BTUs?  The intense lunar cycle, with the sun and moon opposing Pluto?

Was the set temperature 180? What was your HHT? Is it possible to set an LHT that is higher than HHT and if so, what happens? Does it run at LHT? If you try to raise LHT above HHT do they both rise to the same setting?

I ask these questions because I have never used a PG500 or PG1000. The fact you adjusted your LHT up and the temperature in the pit increased leads me to believe it was running at LHT. If LHT and HHT are the same, it will run at that setting no matter the set temperature. It is a feasible explanation as to why the PG500 ran well below the 180 set temperature, if it was set to 180. If HHT was much higher than LLT, this blows this theory completely out of the water.

OMG, Slaga, you're broke the code.  You highlighted my mistake!  I haven't used my PG500 for months and reversed the LHt/HHt definitions.

The HHt is the pellet dropping schedule when the pit is below the set temperature.  LHt is the pilot light used when the pit is above the temperature setting.

I was adjusting the wrong variable!

So your mistake now shows the rest of us how to maintain super low temps.
That could be handy in many situations. How many times have you seen questions from members looking to get low temps?
This wasn't your intent, but what an interesting result.

I would prefer the temps you were at to make jerky.  It will take longer, but I think it may end up with a better product.  Nice discovery for those who have a similar controller.

Glad I was able to help.

Some of the time when I make jerky , I set LHT and HHT to exactly the same... forcing the grill to run manually at one single feed rate, regardless of the temperature.  I do this when I make bacon too... one of the reasons I do this, is to run at temperatures bellow 170F, which can be done on a cool day... 

 But anyway..  yeah, make sure you got your HHT and LHT straight.