FAQs

Yes. Across Canada, all plastic venting systems for gas appliances must be certified to ULC S636, as mandated by Clause 8.9.6 of the CSA B149.1 Natural Gas and Propane Installation Code. This national code is adopted in every province and territory, sometimes with local amendments, but the ULC S636 requirement applies everywhere. Provincial safety authorities (such as TSSA in Ontario, Technical Safety BC, and the Régie du bâtiment du Québec) enforce compliance.

While polypropylene may carry a slight material premium, installers typically save significant time, often up to 70% on labor, because ULC S636 polypropylene vent systems are faster and easier to install. The overall installed cost is often lower compared to alternative venting materials, particularly when factoring in long-term reliability and fewer call-backs.

InnoFlue® polypropylene Special Gas Vent Systems, tested and listed to ULC S636, have been available in Canada since 2009. Polypropylene venting has been widely used in Europe for over 25 years, establishing a proven track record of safety and performance.

ULC S636 certification ensures that:

• The entire venting system (pipe, fittings, and seals) is tested and listed as a complete assembly.
• The system meets strict performance requirements for temperature, pressure, and leakage.
• Only factory-listed components may be used; field-fabricated or mixed-material venting is not permitted.
• The vent system is safe and compliant when installed according to the listing and manufacturer’s instructions.

InnoFlue® ULC S636 venting systems are available from plumbing and HVAC wholesalers across Canada, making them easy to source for contractors and distributors nationwide.

Both standards certify venting systems for use with condensing appliances, but UL-1738 is more stringent than ULC S636. Notable differences include:

• Pressure Testing: UL-1738 tests at 250% of rated operating pressure. ULC S636 has no pressure test requirement.
• Leakage Testing: ULC S636 allows leakage of 0.3 L/h @ 100 Pa, which is at a pressure 24% lower than UL-1738 testing.
• Puncture Test: UL-1738 requires resistance to a steel plunger drop test. ULC S636 does not.
• Low Temperature Handling: UL-1738 requires a -20°C drop test with no cracks or failures. ULC S636 has no cold weather test.
• UV Testing: UL-1738 includes UV and water exposure conditioning before testing. ULC S636 has no UV test.
• High Temperature Testing: UL-1738 requires testing at 38.8°C (70°F) above rated temperature. ULC S636 does not.

We have joined forces with our sister company, Ubbink for our Air Excellent product range. Together, we will continue to offer our state-of-the-art air ventilation system, in Canada. While our business practices remain the same, we are combining the strengths of both brands to further innovate and develop Air Excellent.

Yes. The distribution box includes flow restrictors that allow precise balancing of airflow for each room. This gives homeowners more comfort control, ensures consistent air delivery to every space, and eliminates the need for costly on-site balancing or commissioning.

No. Because Air Excellent is pre-engineered and pressure-calculated, it eliminates the need for field commissioning in most installations. This saves installers time, labor costs, and callbacks, while guaranteeing that the system performs as designed right from installation.

Yes. Centrotherm provides a free design service that calculates airflow restrictions, ensures balanced ventilation, and generates a complete Bill of Materials. This gives installers confidence that every system is engineered correctly before installation, saving time and preventing costly mistakes.

The system uses snap-fit, gasket-sealed connections that make it completely mechanical and airtight. This eliminates the need for duct tape, sealant, or screws, common leakage points in traditional ducting. Airtight ducts mean better energy efficiency, lower operating costs, and quieter system performance.

Yes. Air Excellent is compact and designed to fit within 2x4 or 2x6 stud walls, ceilings, and floors, making it ideal for both new builds and retrofit projects. Its flexibility means minimal demolition in renovations, while the sleek design integrates easily with modern construction methods.

InnoFlue® is approved for gas-fired Category II and IV appliances and is suitable for vertical or horizontal venting in new or retrofit installations, including chimneys, chases, and through-wall terminations. InnoFlue® Polypropylene also meets ULC-S636 code.

Connector Rings are required for an installation of 2″ through 5″ diameter InnoFlue® to be UL-1738 and ULC-S636 compliant. Centrotherm strongly recommends the use of Connector Rings on all installations. Diameters 6″ and larger do not require the use of Connector Rings.

InnoFlue® Polypropylene Special Gas Vent Systems can be field cut to length using a hacksaw and miter box or equivalent. InnoFlue® must be cut on the male end of the pipe, preserving the socketed (female) end. After making a cut, the end can be beveled at the contractor’s discretion. The end must be deburred using a standard deburring tool or sand paper.

Yes, the exterior of InnoFlue® can be painted. Please follow the surface preparation specified by the paint manufacturer.

Yes. For rooftop terminations, follow flashing and sealing instructions. Vertical terminations over 59” above the roof line must be supported with guy wires or braces.

Not directly. For underground applications, InnoFlue® must be installed inside a larger diameter, direct-bury-rated pipe. The vent must be pitched, supported, and allowed to expand/contract inside the sleeve.

Yes, InnoFlue® Flex can be field cut, but only in the rigid sections and when connecting to the female end of Single Wall.

When venting combustion gas, InnoFlue® Flex cannot be installed horizontally. The installation of InnoFlue® Flex in a horizontal configuration allows for the pooling of condensate. This can create sagging in the vent system leading to the creation of back pressure. Back pressure can result in a forced shut down of the heating appliance. InnoFlue® Flex and BlitzFlex® can be installed horizontally when used as an air intake.

InnoFlue® Flex can be installed in a shared chimney, assuming the flues are separated, if the ambient air temperature does not exceed 300°F (149°C).

InnoFlue® Flex should not be installed in a sheet rock wall.

InnoFlue® Polypropylene Special Gas Vent Systems can be installed in chases with offsets that do not exceed 45°. Chases can have multiple offsets.

No, InnoFlue® Flex is ULC-S636 listed exclusively for use as a combustion gas vent system inside of a chase.

The InnoFlue® Concentric vent kit must always be installed according to Centrotherm’s official installation instructions to ensure safety, compliance, and system performance.

The concentric vent system can be installed in a variety of chases, including masonry, B-vent, and sheet rock chases, offering flexibility for different construction types.

InnoFlue® Concentric vent kit combines exhaust gas venting and combustion air intake into a single concentric vent system. This design allows for a cleaner, more aesthetically pleasing installation, reduces the number of roof or wall penetrations, and helps save on labor and installation time.

A concentric vent is a type of venting system that incorporates both exhaust and intake air in one pipe-within-a-pipe design. The InnoFlue® Concentric vent kit features a durable metal outer with a polypropylene inner. Combustion gas is drawn through the space between the two pipes, while exhaust gases are safely expelled through the polypropylene inner pipe.

The InnoFlue® Concentric vent system is engineered to withstand flue gas temperatures up to 230°F (110°C).

InnoFlue® Concentric vent kits are approved for use with gas-fired Category II and Category IV appliances, making them versatile for residential and commercial applications.

InnoFlue® Lite is a lightweight, CE EN 14471-certified polypropylene venting system designed for use with Category II and IV gas-fired appliances in the U.S. and for air intake applications only in Canada, as it does not meet ULC S636 requirements for exhaust venting.

Yes, InnoFlue® Lite is the perfect solution for air intake in Canada.

No InnoFlue® Lite does not meet ULC S636 requirements for exhaust venting. However, it can be used for air intake, being price comparible to PVC.

Yes. Use paints approved for polypropylene, such as Rust-Oleum or Krylon. Remove ink markings with acetone, apply an appropriate adhesion promoter, and reattach the product label once dry.

Use Centrotherm-supplied support brackets when possible. Horizontal runs must be supported every 39" (1 m); vertical runs must be supported every 78" (2 m). Directional changes (elbows/tees) should be supported within 12".

Yes. All components are factory-equipped with gaskets. If a gasket is damaged or missing, replace it with a genuine Centrotherm part. Clean gaskets and gasket beads before assembly.

For exhaust applications using 2", 3", and 4" diameters, all joints must use either OctoClamps or Connector Rings. For air intake, the OctoClamp is optional on every joint and should be used as needed to properly support the system.

The OctoClamp is a support and joint-securing component designed for Centrotherm InnoFlue® and InnoFlue® Lite. It helps secure joint connections and support the vent run when used with the OctoClamp Hanger or 3/8”-16 threaded rod.

The OctoClamp Hanger is a support designed to attach to joists, studs, or other solid surfaces in multiple orientations in combination with the OctoClamp.

The OctoClamp is designed to connect directly with 3/8"-16 threaded rod. The threaded rod can be threaded into the OctoClamp’s connection feature, or the OctoClamp can close around the threaded rod while connecting to the pipe.

The OctoClamp is permitted for use with 3/8"-16 threaded rod in horizontal support applications only. It must not be used with threaded rod in vertical support applications. For proper installation requirements and limitations, refer to the official installation instructions.

When used together, the OctoClamp and OctoClamp Hanger create an integrated vent support solution that secures vent joints while also helping support the vent system. This allows for a clean, adaptable installation in both horizontal and vertical applications.

The OctoClamp Hanger allows for OctoClamp installation in a variety of different directions. For all orientations refer to the installation instructions.

For standard InnoFlue horizontal installations, two OctoClamp Hangers may be connected
to extend the length if additional reach is needed. Do not connect more than two OctoClamp Hangers in a single chain.

Effective February 1, 2027, Centrotherm is simplifying its part number hierarchy so that each product will have one part number, regardless of whether it is ordered as an individual unit, a carton, or a pallet.

Previously, separate part numbers were used for different packaging quantities. Under the new hierarchy, all packaging levels of the same product will share one part number, making ordering and inventory management simpler.

This update is designed to simplify ordering, reduce the number of part numbers, and improve the purchasing experience for our customers.

By consolidating packaging levels under a single part number, we aim to reduce confusion, streamline order processing, and make purchasing larger quantities easier.

Simply order the quantity you need using the Centrotherm part number listed in our updated price list. Our ordering system will automatically calculate the appropriate packaging configuration based on the quantity ordered.

For example, if you order 30 units of a product supplied in cartons of 25, your order will be fulfilled as one carton of 25 units and five individual units.

You no longer need to select separate part numbers for different packaging quantities.

No. From February 1, 2027, the separate carton and pallet part numbers will no longer be available for ordering.

Instead, you will use the single part number assigned to the product and enter the total quantity required. Our system will handle the packaging calculations automatically.

For example, if you wanted to order 5 units of ISELL0487, you previously had to order 1 carton (ISELL0487-4) and 1 individual unit (ISELL0487). With the new system, you simply order 5 units using ISELL0487, and our system will automatically determine the appropriate packaging configuration. The same process applies to products with pallet quantities, making it easier to order the quantities you need without having to select separate part numbers for cartons or pallets.

If you need help adjusting to the new ordering process, our Customer Service team will be happy to assist.

Centrotherm single unit part number will remain unchanged. However, the separate part numbers previously used for cartons and pallets will be discontinued.

Depending on how your system manages product information and inventory, you may need to review your existing product records and item mappings to accommodate the updated structure.

If you have questions about how the change may affect your processes, please contact our Customer Service team for assistance.

The current UPC/GTIN numbers will remain unchanged for the various packaging levels. This will help to streamline both order entry and receiving for our customers. 

For customer working with only the single item number, all inventory will now function under that item number and for customers working with various packaging levels, the unique GTIN numbers will allow for scanning of each unique packaging level.

Centrotherm partners with one third-party logistics (3PL) facility in Canada, in Vancouver, British Columbia.

Vancouver, BC
211–19265 Airport Way
Vancouver, BC

You can find more information here. 

You should only send a driver after receiving confirmation that the order is ready for pickup. An order acknowledgment or order entry confirmation does not guarantee that the order has been picked, staged, or prepared for pickup.

Before the driver arrives, make sure they have the following information:

• 3PL warehouse name and address
• Customer or company name
• PO/Sales Order Number
• Pickup reference number, if applicable
• Any specific pickup instructions provided by Customer Service

All pickups should occur during the 3PLs designated pickup hours. If an after-hours pickup or special arrangement is required, contact Centrotherm Customer Service in advance and ensure the request has been confirmed before sending the driver.

Allow sufficient time for the 3PL to locate, stage, and load the order. Loading times may vary depending on the order size, warehouse volume, and equipment availability. Drivers should not expect their orders to be loaded immediately upon arrival.