My belief is the two biggest factors you will see when buying a bag of pellets are:

A)  Moisture content.  This will vary buy several percentage points and since you are buying by weight, the higher water content, the less wood you will get per bag.  Also, chances are the higher moisture content will also lower your burn temperature or increase the amount of pellets you will use.

B)  Ash content.  Ash doesn't burn.  The higher non-burnable product you have (non-flammable impurities) the more non-burnable wood you will have in a bag of pellets.


Some math:
Gas grills can range from 35,000 BTU per hour to 50,000+.
For ease of math, we'll say we are running our pellet grills for an hour at a temperature that makes us use 24,000 BTU per hour.

To get the 24,000 per hour you would need the following amount of flammable wood to get 24,000 BTU in that hour.

A 6,000 BTU wood = 4 lbs
A 7,000 BTU wood = 3.5 lbs
A 8,000 BTU wood = 3 lbs of flammable wood burned.

If you 8,000 BTU wood was at 15% ash and moisture (total combined), you're using close to 3.5 lbs of pellets.
Also, if your moisture percentage will be 8% or less, so you have less water in your burn which would affect temperature differences between two similar woods.
It's unknown what an additional 7% of water / ash will do to a fire, but my assumption is that it would burn cooler / use more pellets.

PFI certifies pellet fuels on moisture and ash where bbq pellets are unregulated so you don't really know what you are getting since they aren't tested.

From using both, I've seen from my own experience the massive reduction in ash and less pellet usage from burning PFI certified pellets (not to mention the much lower cost).
If I want a specific smoke flavor, I use a smoke tube with a few ounces of bbq pellets rather than burn pounds and pounds of them as a heat source.

Even if different pellets produced more or less heat that could lead to some temp swings but not an overall higher or lower temp as that is what the controller in a pellet smoker is for right?  I mean, lets say you ran a "hot pellet".  Set point is 225.  Feeds in pellets at a set rate based on the controller.  Oops temp jumps due to "hot pellet".  So controller stops feed, temp, falls, repeat.  The opposite would happen with a "cool burning pellet".  But either way the difference can't possibly be that significant given how tight some of these controllers are.

Even if different pellets produced more or less heat that could lead to some temp swings but not an overall higher or lower temp as that is what the controller in a pellet smoker is for right?  I mean, lets say you ran a "hot pellet".  Set point is 225.  Feeds in pellets at a set rate based on the controller.  Oops temp jumps due to "hot pellet".  So controller stops feed, temp, falls, repeat.  The opposite would happen with a "cool burning pellet".  But either way the difference can't possibly be that significant given how tight some of these controllers are.

That would depend on the controller. Digital - yes. PID - no.

My belief is the two biggest factors you will see when buying a bag of pellets are:

A)  Moisture content.  This will vary buy several percentage points and since you are buying by weight, the higher water content, the less wood you will get per bag.  Also, chances are the higher moisture content will also lower your burn temperature or increase the amount of pellets you will use.

B)  Ash content.  Ash doesn't burn.  The higher non-burnable product you have (non-flammable impurities) the more non-burnable wood you will have in a bag of pellets.


Some math:
Gas grills can range from 35,000 BTU per hour to 50,000+.
For ease of math, we'll say we are running our pellet grills for an hour at a temperature that makes us use 24,000 BTU per hour.

To get the 24,000 per hour you would need the following amount of flammable wood to get 24,000 BTU in that hour.

A 6,000 BTU wood = 4 lbs
A 7,000 BTU wood = 3.5 lbs
A 8,000 BTU wood = 3 lbs of flammable wood burned.

If you 8,000 BTU wood was at 15% ash and moisture (total combined), you're using close to 3.5 lbs of pellets.
Also, if your moisture percentage will be 8% or less, so you have less water in your burn which would affect temperature differences between two similar woods.
It's unknown what an additional 7% of water / ash will do to a fire, but my assumption is that it would burn cooler / use more pellets.

PFI certifies pellet fuels on moisture and ash where bbq pellets are unregulated so you don't really know what you are getting since they aren't tested.

From using both, I've seen from my own experience the massive reduction in ash and less pellet usage from burning PFI certified pellets (not to mention the much lower cost).
If I want a specific smoke flavor, I use a smoke tube with a few ounces of bbq pellets rather than burn pounds and pounds of them as a heat source. Right on brother..

My belief is the two biggest factors you will see when buying a bag of pellets are:

A)  Moisture content.  This will vary buy several percentage points and since you are buying by weight, the higher water content, the less wood you will get per bag.  Also, chances are the higher moisture content will also lower your burn temperature or increase the amount of pellets you will use.

B)  Ash content.  Ash doesn't burn.  The higher non-burnable product you have (non-flammable impurities) the more non-burnable wood you will have in a bag of pellets.


Some math:
Gas grills can range from 35,000 BTU per hour to 50,000+.
For ease of math, we'll say we are running our pellet grills for an hour at a temperature that makes us use 24,000 BTU per hour.

To get the 24,000 per hour you would need the following amount of flammable wood to get 24,000 BTU in that hour.

A 6,000 BTU wood = 4 lbs
A 7,000 BTU wood = 3.5 lbs
A 8,000 BTU wood = 3 lbs of flammable wood burned.

If you 8,000 BTU wood was at 15% ash and moisture (total combined), you're using close to 3.5 lbs of pellets.
Also, if your moisture percentage will be 8% or less, so you have less water in your burn which would affect temperature differences between two similar woods.
It's unknown what an additional 7% of water / ash will do to a fire, but my assumption is that it would burn cooler / use more pellets.

PFI certifies pellet fuels on moisture and ash where bbq pellets are unregulated so you don't really know what you are getting since they aren't tested.

From using both, I've seen from my own experience the massive reduction in ash and less pellet usage from burning PFI certified pellets (not to mention the much lower cost).
If I want a specific smoke flavor, I use a smoke tube with a few ounces of bbq pellets rather than burn pounds and pounds of them as a heat source.

Even if different pellets produced more or less heat that could lead to some temp swings but not an overall higher or lower temp as that is what the controller in a pellet smoker is for right?  I mean, lets say you ran a "hot pellet".  Set point is 225.  Feeds in pellets at a set rate based on the controller.  Oops temp jumps due to "hot pellet".  So controller stops feed, temp, falls, repeat.  The opposite would happen with a "cool burning pellet".  But either way the difference can't possibly be that significant given how tight some of these controllers are.

That would depend on the controller. Digital - yes. PID - no.

Can you elaborate.  Did you mean analog vs. PID?  I thought PID controllers were inherently digital.

Even if different pellets produced more or less heat that could lead to some temp swings but not an overall higher or lower temp as that is what the controller in a pellet smoker is for right?  I mean, lets say you ran a "hot pellet".  Set point is 225.  Feeds in pellets at a set rate based on the controller.  Oops temp jumps due to "hot pellet".  So controller stops feed, temp, falls, repeat.  The opposite would happen with a "cool burning pellet".  But either way the difference can't possibly be that significant given how tight some of these controllers are.

Right.  The hotter burning pellet would use less pellets because the controller will slow down the auger and feed less pellets.

That's why I see less pellet usage, (probably due to less moisture) and way less ash, when using heating pellets over BBQ pellets.

Even if different pellets produced more or less heat that could lead to some temp swings but not an overall higher or lower temp as that is what the controller in a pellet smoker is for right?  I mean, lets say you ran a "hot pellet".  Set point is 225.  Feeds in pellets at a set rate based on the controller.  Oops temp jumps due to "hot pellet".  So controller stops feed, temp, falls, repeat.  The opposite would happen with a "cool burning pellet".  But either way the difference can't possibly be that significant given how tight some of these controllers are.

That would depend on the controller. Digital - yes. PID - no.

Can you elaborate.  Did you mean analog vs. PID?  I thought PID controllers were inherently digital.

A PID is analog.  Proportional, Integral, and Derivative controllers go back 100+ years in industry.  Long before digital computers existed.  Today's PID controllers use a digital computer that simulates the PID functions.  The functions themselves are still analog in nature. 

There may also be a digital display of the temperature, and some manufactures use the term "Digital" to describe that.

There are other algorithms that are purely digital, and do not mimic the PID functions.  I am not an expert on these, but I do know they exist.  I think some pellet grills may use these purely digital algorithms.  I suspect when a manufacturer states that the controller is digital and uses something other than PID, that this is what they use.