The AllFuel HST kits are the listed options designed for an 8-inch through-the-wall chimney installation. They share the same stated compatibility and support guidance, but come with different chimney-pipe lengths: 9, 12, 18, or 24 inches. Choose the length based on your measured wall and installation layout. The DuraVent kit is included as a brand comparison, but it is specified for 6-inch pipe—not 8-inch systems.
| Kit | Stated pipe size | Best suited for |
|---|---|---|
| AllFuel HST, 9-inch length | 8 inches | Layouts needing the shortest listed length |
| AllFuel HST, 12-inch length | 8 inches | Layouts needing a middle-length option |
| AllFuel HST, 18-inch length | 8 inches | Layouts needing a longer listed length |
| AllFuel HST, 24-inch length | 8 inches | Layouts where a longer length fits the measured wall |
| DuraVent DuraPlus kit | 6 inches | Comparison only; not an 8-inch match |
AllFuel HST 9-Inch Through-The-Wall Kit
This kit is listed for 8-inch AllFuel HST Class-A double-wall insulated chimney pipe and includes a spark-guard chimney cap and adjustable wall bracket. The chimney pipe lengths needed for the full installation are sold separately. The adjustable bracket extends up to 7 inches, which can help when a gutter or small overhang affects bracket placement.
Best for: Buyers whose measured wall and setup call for the 9-inch length. It is the shortest listed AllFuel HST option here. Follow the product guidance to measure wall thickness and add the stated allowance: at least 5 inches when the pipe is exposed outside, or 8 inches when enclosed in a chase.
Limitation: It cannot connect to other brands of Class-A chimney pipe. Additional wall brackets may be needed depending on chimney height.
AllFuel HST 12-Inch Through-The-Wall Kit
The 12-inch version is another 8-inch AllFuel HST kit with a spark-guard cap and adjustable wall bracket. It uses the same brand-specific Class-A chimney system as the other AllFuel options, and additional pipe lengths are sold separately.
Best for: Buyers who have measured their wall and determined that a 12-inch length suits the pass-through. It provides a middle option between the listed 9-inch and 18-inch lengths, making it useful when neither shorter nor longer version fits the planned route.
Limitation: The listed product information does not establish that it fits another chimney brand. Confirm the complete system requirements before ordering.
AllFuel HST 18-Inch Through-The-Wall Kit
This kit is specified for 8-inch AllFuel HST Class-A double-wall chimney pipe and includes a spark-guard chimney cap and adjustable wall bracket. The bracket can extend up to 7 inches to clear a gutter or small overhang. Separate chimney pipe lengths are required for the rest of the installation.
Best for: Buyers whose measured pass-through calls for the longer 18-inch option. Compare it with the 12-inch and 24-inch versions using actual wall thickness and the manufacturer’s stated allowances rather than choosing by length alone.
Limitation: This is not listed as compatible with other brands of Class-A pipe. The product information also says a wall bracket is required for every 8 feet of vertical rise above the base wall support; extras may need to be purchased separately.
AllFuel HST 24-Inch Through-The-Wall Kit
The 24-inch version is the longest listed AllFuel HST option in this group. It is designed for 8-inch AllFuel HST Class-A double-wall chimney pipe and comes with a spark-guard cap and adjustable wall bracket. Additional chimney pipe lengths are sold separately.
Best for: Buyers whose measured installation requires a longer pass-through length and whose chimney system uses AllFuel HST components. The adjustable bracket is useful to consider when a small overhang or gutter affects exterior support placement.
Limitation: A longer kit length does not remove the need to verify the wall dimensions and required clearances. It is not listed as compatible with other brands.
DuraVent DuraPlus 6-Inch Wall Kit
This DuraVent kit is specified for 6-inch DuraPlus chimney pipe, so it is not a direct match for an 8-inch stove-pipe search. Its listed features include a through-the-wall vertical chimney installation design, a twist-lock connection, and support for up to 40 feet of chimney pipe, which is not included.
Best for: Buyers comparing a DuraPlus option for a 6-inch system, not shoppers who need an 8-inch kit. It is included to make the size mismatch clear.
Limitation: Do not select it for an 8-inch installation based on the available product information; its stated pipe size is 6 inches.
Buying Guide: How To Choose An 8-Inch Through-The-Wall Kit
Which pipe length should you choose?
Measure the wall thickness at the planned chimney pass-through. All four 8-inch AllFuel HST listings advise adding at least 5 inches if the pipe will be exposed outside the house, or 8 inches if it will be enclosed in a chase. Use those figures as the listed product guidance, and verify the exact installation requirements before buying. The available lengths are 9, 12, 18, and 24 inches.
Does the kit match your chimney brand?
The AllFuel HST kits are stated to work with AllFuel HST Class-A double-wall chimney pipe and not other brands of Class-A chimney. Do not assume that matching the diameter alone makes components interchangeable. The DuraVent item is a 6-inch DuraPlus kit, so it is not a listed 8-inch alternative.
What should you check about the support bracket?
The AllFuel HST kits have an adjustable bracket that extends up to 7 inches to pass a gutter or small overhang. The product details say a wall bracket is required for every 8 feet of vertical rise above the base wall support. Additional brackets may be purchased separately if the installation needs more than one.
Are the pipe lengths included?
The AllFuel product descriptions state that chimney pipe lengths are sold separately. Check the parts list for the complete installation, including the pipe sections and any extra support brackets required. The DuraVent listing also says its chimney pipe is not included.
Frequently Asked Questions
Are all four AllFuel kits made for 8-inch chimney pipe?
Yes. Each listed AllFuel HST kit is specified for 8-inch AllFuel HST Class-A double-wall chimney pipe. Their included length options differ.
Can an AllFuel HST kit connect to another Class-A brand?
The product details say these kits cannot connect to other brands of Class-A chimney. Confirm system components with the manufacturer before combining parts.
Is the DuraVent kit suitable for an 8-inch installation?
No. The listed DuraVent DuraPlus kit is for 6-inch chimney pipe, so it is not an 8-inch match.
How often are additional AllFuel wall brackets needed?
The listed guidance calls for a wall bracket for every 8 feet of vertical rise above the base wall support. Extra brackets may need to be purchased separately.