Wood Pellet Knowledge

Wood pellets are the fuel that provides both the heat and smoky flavour in a Z Grills pellet smoker. In this article you will learn everything you need to know about them!

Wood pellets burning in Z grills pellet smoker fire-pot

Wood varieties

Not just any type of wood is suitable for a wood pellet smoker. Wood varieties are chosen that provide a nice smoky flavour when burnt and include both hardwoods and many fruit woods.

Wood varieties can be mixed to create a blended wood pellet. Some wood types provide a very subtle flavour, whilst others like mesquite are much more powerful.

Wood pellets for Z Grills Pellet Smokers

It is important to only use wood pellets designed for wood pellet smoker grills, and not pellets used for heating furnaces as they will make the food taste terrible!

In Australia we are lucky to have locally grown Aussie hardwood wood pellets that may include varieties such as Yellow Stringy Bark, Grey Box, Flooded Gum and Ironbark. What’s even better these pellets are made from scrap wood shavings that would otherwise go to waste.

Other popular wood varieties include:

  • Cherry
  • Apple
  • Pecan
  • Hickory
  • Oak
  • Maple
  • Mesquite

Additional flavours can be added to wood pellets by adding herbs into the mix, or even including woods from barrels used to store alcohol such as wine or port.

It is perfectly fine to mix different wood pellet varieties. So adding some Hickory into a base of Aussie hardwood might be worth trying!

Wood pellet production

Wood pellets are made from shredded wood fibre that is extruded through a die at high pressure. During this process the pressure and friction heats up the wood to over 100℃ melting the lignin in the wood. As the pellets cool the lignin acts like a glue to hold the wood together once cooled back down.

No chemicals or additives are needed to form the wood pellets.

Click here to learn more about lignin.

Best wood pellet brands

While we haven’t tried every type of pellet on the market here in Australia, below is a basic guide for some commonly available brands that we have used. If you have any suggestions please let us know.

Smokin’ Pellets (Aussie hardwood)GOOD
Ministry of Smoke (Aussie hardwood)GOOD
Firebrand (Aussie hardwood)GOOD
Vios Victorian Ash (Aussie hardwood)GOOD
BBQrs DelightGOOD
Heat BeadsGOOD
Green Mountain GrillsOK
Bear MountainNot Recommended (high ash)
Jack Daniels Not Recommended (high ash)

The “Not recommended” brands listed above are primarily for the reason of high ash which can rapidly fill the fire-pot, causing fire-out or smoky hopper issues. The problem with these pellets is based on feedback from many users, but may have been limited to certainly production batch so if you have had good experience with these please let us know.

If you like the flavour a high ask pellet provides, consider using them in a smoke tube to provide addition smoke together with that coming from the Z Grill fire-pot.

Can heating wood pellets be used?

No! Wood pellets for heating are not suitable and will make the food taste terrible.

Maximise smoky flavour

Maximise smoky flavour by running the grill on the SMOKE setting for the first 30-90 minutes of the cook (or even longer if you wish) before then taking the temperature up to the standard low ‘n’ slow cooking temps of 107ºC / 225ºF or 121ºC / 250ºF.

Wood varieties will provide different (although mostly subtle) flavour differences. Hickory and Mesquite provide a strong smoky flavour.

Z Grills Smoke Tube
Z Grills smoke tube for even more smoky flavour

For even more smoky flavour a smoke tube (as shown above) can also be used. They are a good option when using more powerfully flavoured wood varieties, or those that might have good flavour but are too high in ash for reliable use in your Z Grills smoker (see list here).

Click here to learn more about smoky flavour and how much smoke to expect from your Z Grills smoker.

Where to buy wood pellets

Check our Facebook group or other BBQ groups/forums for availability of quality pellets in your local area, as delivery costs can be high due to the weight.

We stock pellets in our warehouses which can be purchased online when buying a Z Grills or via the 4 bag bulk buy option for warehouse collection only (no shipping options).

The pellets types in stock varies across the warehouses, so feel free to contact us before the order to confirm what we have available.

Pellet delivery by auger

An auger motor connects to the end of a spiral auger shaft that feeds wood pellets from the hopper through a feed tube into the fire-pot.

Z Grills smoker auger motor turning auger

The auger shaft rotates the auger very slowly, only 1.6 RPM (revolutions per minute) for most Z Grills models.

The controller turns the auger motor on/off intermittently to supply wood pellets into the fire-pot to reach, and then maintain the set temperature.

A small fan on the front of the auger motor cools the motor, not to be confused with the large fan underneath the hopper that supplies air to the fire-pot.

Noisy auger & pellets

Sometimes a wood pellet can become stuck between the auger shaft and wall of the feed tube making a grinding or squeaking noise. As long as the auger is still turning intermittently there is nothing to worry about and the noise should stop once the pellet makes it way through into the fire-pot.

A clunking sound make also be heard as longer pellets are broken in half by the auger as they enter the mouth of the feed tube. This is also normal.

It is very uncommon that a pellet becomes so jammed that the auger cannot rotate. If you think that may be the case, click here to learn how to clear it.

Loose Auger Motor and Shaft

The auger motor and auger shaft are mounted with lots of free movement to allow pellets to be effectively pushed through into the fire-pot.

Lighting pellets with ignition rod

An ignition rod (also know as a hot rod) is located in a tube in the bottom of the fire-pot and gets red hot to ignite (light) the wood pellets.

SN ignition rod glowing in fire-pot
Red hot silicon nitride ignition rod

The ignition rod runs for about 5 minutes when the Z Grills is first turned on (from Shut Down to Smoke) and then at times during operation if the temperature drop suddenly, or below a certain temperature to prevent the fire going out.

There are two types of ignition rods may be installed in your Z Grills smoker. Click here to learn more.

Wood Pellet Usage Rate

The rate at which wood pellets are used is directly linked to the amount of heat loss from the grill to the surrounding air.

The larger the temperature difference, the more pellets will be required to maintain the grill temperature (ie. heat produced = heat loss).

Factors that impact pellets usage include:

  • Cold weather = more pellets used
  • High grill temperatures = more pellets used
  • Windy conditions = more pellets used
  • Hot weather = less pellets used
  • Direct sunlight = less pellets used
  • Type of wood pellet. Hardwoods tend to have more heat/kg than softwoods, so will last longer at a given operating temperature.

Pellet hourly usage rate

Mini (portable) grill:

  • Low temperature operation = 0.15 to 0.25kg/hour (0.33 to 0.55lbs)
  • High temperature operation = 0.5 to 1kg/hour (1.1 to 2.2lbs)

450A, 7002B and 700E-XL grills:

  • Low temperature operation = 0.3 to 0.5kg/hour (0.7 to 1.1lbs)
  • High temperature operation = 1 to 2kg/hour (2.2 to 4.4lbs)

How to reduce pellet usage?

  • In cold weather an insulating cover can be used to significantly lower heat loss and reduce pellet usage.
  • Avoid opening the lid too much which releases heat
  • Keep the grill out of the wind

How many pellets to add into the hopper?

Z Grills smokers only use as many pellets as required to maintain the set temperature, so once a cook is over there may be wood pellets left in the hopper.

There is no need to fill the hopper right up unless doing a very long cook (we are talking 20+ hours). After using your Z Grills smoker a few times you will learn how many pellets are used and so know what level is required for a cook.

In humid climates avoid having pellets sitting in the hopper for a long time as they can absorb moisture, so only add as many pellets as required for the cook (plus a bit extra to avoid running out).

It is a good habit to regularly run the grill until all pellets are depleted and the fire goes out, then give it a good clean. Click here for more information.

Storing wood pellets

Keep pellets dry!

It is important to keep wood pellets in a sealed container or bag to avoid absorbing moisture. This is particularly important for humid environments.

Wood pellets stored in plastic container

Wood pellet plastic bags have small pin holes to let the air out, but these can also let moisture in if in direct contact with wet surfaces. Do NOT sit bags of wood pellets directly on any surface that could be moist (due to rain or condensation), especially concrete.

Do not use the hopper as a place to store pellets long term. Only pour in as many as required for the next cook. See the next section on this too.

Wet pellets

Below shows cherry pellets after being exposed to some light rain. They become soft and mushy. This can happen over time if exposed to high humidity.

For this reason pellets should always be stored in a sealed container.

Wet wood pellets in bag

Below shows nice dry pellets (left) and ones that have become wet (right) in the bottom of the hopper. Dry pellets appear smooth and shiny and are very hard and should not easily crumble in your hands.

Wood pellets dry and wet in auger

Trying to use moist pellets will result in very inconsistent operation with the fire unable to be established, or the fire may even go out which can cause issues.

Left to sit in the hooper and auger feed tube, wet pellets can dry and set like concrete, requiring a full auger clean.

If you notice they are moist or any water drips in there, immediately clean out the hopper and run the grill on high to clear out all pellets. Vacuum out the hopper and fire-pot and start with fresh dry pallet, following the initial startup procedure to prime the auger feed tube with pellets.

Wood dust

Lots of wood dust in the hopper can lead to temperature spikes, excess smoke and even burn-back resulting in a smoky hopper.

We recommend pouring the bag of pellets into a bucket/container and scoop from the top when adding to your hopper. The dust will settle to the bottom and you can just tip out on the garden once the container is empty.

Storing them in the bag can still lead to moisture issues as the bag has pin holes and so will breath outside air in/out as the temperature changes.

Running the wood pellets completely out and vacuuming the bottom of the hopper every 40 to 50kg used is also a good idea. Click here to learn how.

Cleaning out pellets

Z Grills smokers will only use as many pellets as required to maintain the temperature. Depending on the starting pellet quantity in the hopper and length of the cook, there will normally be pellets left in the hopper which can be used next time the grill is used. They do not need to be removed after each cook, but should be removed if not using the grill for several weeks or longer.

In humid climates, leaving pellets sitting in the hopper for even a couple of weeks could be an issue as they can absorb moisture. This will become apparent if the pellets do not burn well, in particular if they struggle to reach the desired temperature or the fire goes out.

If not planning to use the grill for several weeks or longer, it is a very good idea to scoop out all the remaining pellets (temporarily remove the protective guard if required).

Two small screws under the lid of the guard

There are two small screws under the front and rear lid of the guard as shown below. With those removed the guard can be lifted out, making it easy to scoop the pellets out right to the bottom.

Plastic scoop, mug or bowl work great to scoop pellets out

With most of the pellets used up (or scooped out) of the hopper, fire up and run the grill until all the pellets are feed into the fire-pot and the fire eventually goes out.

Once the fire has gone out and the temperature drops, the grill will eventually show a LER (low temperature ) error on the screen (which is ok). Just turn the dial to Shut Down and the power switch OFF.

Once the grill has cooled down, vacuum out the bottom of the hopper of wood dust and the the fire-pot and grill drum of ash.

Click here for more information about cleaning a Z Grill.

A pellet dump that allows you to empty the hopper from a trap-door in the back of the hopper is a feature that some grill models on the market have. Aussie Z Grills don’t currently have pellet dumps. While they are a nice feature, the reality is they don’t really save much time, and still leave pellets in the bottom of the hopper so the same process of running the grill until all burnt out applies (as explained above).

It is a good habit to only add as many pellets at required for the cook (without running out) instead of filling the hopper up to the top each time. Filling the hopper right up may result in the pellets sitting for extended periods of time potentially absorbing moisture.

Sandy biscuits in fire-pot

After operating the Z Grills smoker at high temperatures, minerals like silica in the wood can melt and then stick together to form a chunk, almost like a flat biscuit of hard, sandy material. It may even have shiny glass-like surfaces, like shown in the example below.

fire-pot sandy glass biscuit
Sandy glass biscuit from fire-pot

These will only occur with certain varieties of wood and are nothing to be concerned about. Just break these up carefully and vacuum out. These biscuits can form fairly quickly, so if using a pellet that is know to cause them, be sure to clean out the fire-pot after every cook.

While cleaning out the fire-pot be careful not to heavily knock the ignition rod at the base of the fire-pot as it can be damaged.