Built Environment & Transport

HVAC & Refrigeration Gaskets

Start with the refrigerant, lubricant, pressure cycle and joint.

A refrigerant name does not select a gasket. Send the equipment model or controlled drawing, exact refrigerant and lubricant, design and standstill pressure, temperature cycle, flange or groove details, decompression duty and required documents. Air-side work needs different inputs: duct construction, seal or leakage class, joint profile and installed test method. We will confirm the quotation boundary before a product is offered.

15% Bulk-HFC baseline quota from 2036
Exact fluid Refrigerant plus lubricant
Exact joint Pressure and temperature cycle
Before quote Evidence and source confirmed
Two Sealing Domains

Air-Side and Refrigerant-Side Are Different Problems

Air-Side Sealing

Ductwork flanges, air-handling-unit access panels, rooftop-unit curb seals and building-envelope penetrations need a defined joint and leakage target. A SMACNA seal class identifies which joints, seams and penetrations are sealed. It does not require a gasketed flange or define the duct pressure. Specify the accepted sealing method and installed test.

Confirm: duct construction · leakage class · seal class · test method

Refrigerant-Side Sealing

Compressor gaskets, plate heat exchanger seals, valve bonnets and piping connections are controlled by the equipment or piping design. CO₂ can create permeation and rapid-gas-decompression risks in some elastomers. Copper-bearing materials are generally excluded from applicable ammonia-wetted service. Neither caution establishes a universal material or gasket construction.

Confirm: exact compound · lubricant · pressure cycle · OEM approval

Refrigerant Transition Alert

Australia's bulk-HFC import quota reduces to 15% of baseline from 2036. A separate rule from 1 July 2025 restricts manufacture or import of defined multi-head split and VRF outdoor units for stationary comfort cooling when the HFC GWP exceeds 750 and the charge is no more than 2.6 kg, subject to the legislation and exemptions. It is not a blanket R-410A installation, sale or service ban. Charge and mitigation requirements depend on the exact equipment, refrigerant safety class, occupancy or access category, geometry and applicable appliance or system standard. Use the OEM's approved seal or exact compound evidence for the complete refrigerant and lubricant duty.

Sub-Sectors We Serve

From Rooftop Units to Blast Freezers

Commercial HVAC

Air-handling-unit access panels, duct flanges, chiller plant piping and rooftop-unit weather seals each need their own joint detail. Provide the duct or equipment drawing, pressure, temperature, required seal or leakage class, surface condition, weather exposure and installed test method.

Industrial Refrigeration

Ammonia and CO₂ systems can involve toxic, flammable or high-pressure duties, but the architecture and component limits vary. Obtain the OEM or piping-design specification, refrigerant and lubricant, design and standstill pressure, temperature range, connection type and decompression duty before screening a gasket.

Chillers & Heat Exchangers

Plate heat exchangers, compressor covers and chilled-water piping all use equipment-specific joints. Provide the manufacturer and model, plate or part code, current gasket, fluid duty, cleaning regime and drawing. We will confirm whether a replacement route and the required evidence are available without implying OEM manufacture or equivalence.

Building Envelope & Specialist

Equipment-panel seals, HEPA filter frames, coolroom doors and cooling-tower joints have different hygiene, weathering, condensation and compression requirements. State the equipment detail, temperature range, cleaning chemicals, airflow or water boundary, target life and validation method.

Technical Questions

Refrigerant Compatibility and Material Selection

R-32 alone does not select a gasket. Start with the equipment manufacturer's approved part or compound, then check the exact formulation, cure and fillers, refrigerant, lubricant and additive concentrations, pressure-temperature cycle, exposure time, compression, ageing, decompression duty, geometry and acceptance criteria. Polymer-family data is only a screening aid.

Use the OEM or piping-design specification for the actual joint. Copper-bearing materials are generally excluded from applicable ammonia-wetted service, but that caution does not approve a universal PTFE, elastomer or metallic-gasket recipe. Confirm the exact alloy or compound, lubricant, pressure, temperature and joint construction.

Obtain the system's design and standstill pressures, temperature range, architecture, flange or connection design and decompression duty. CO₂ permeation and rapid-gas-decompression risks require exact compound and component evidence. They do not make every elastomer unsuitable or establish a universal Spiral Wound Gasket, Kammprofile Gasket, Ring Joint Gasket or PTFE answer.

Published results apply only to the tested compound, refrigerant, lubricant, exposure and acceptance criteria. The 2018 paper in Purdue's conference repository was authored by Shrieve Chemical personnel; it does not establish a universal ranking of FKM, silicone, EPDM and HNBR. Use exact OEM or compound-supplier evidence.

Use the class stated by the project designer or specification. A SMACNA seal class identifies which joints, seams and penetrations are sealed; it does not define pressure class or require a gasketed flange. Confirm the specified edition, duct construction, leakage class, test method and accepted sealing method.

Only when the exact product is intended to contact drinking water within the applicable plumbing installation. A potable make-up connection does not automatically place every downstream chilled-water or cooling-tower gasket inside that boundary. Check the hydraulic design, backflow protection, product location and project requirements. If evidence is required, it must cover the exact product and intended use.

Materials

Material Families Are the Start of the Check

Closed-Cell Neoprene

A candidate for some air-side panel, duct and vibration-isolation joints. Confirm the exact product's cell structure, density, compression range, water absorption, adhesive, weather exposure and installed leakage test.

Screen the exact foam product

EPDM

A candidate for selected outdoor, water and refrigerant duties. Refrigerant suitability cannot be inferred from the polymer name: check the exact compound with the fluid, lubricant, additives, pressure-temperature cycle and exposure time.

Compound data controls

HNBR

HNBR compounds are used in some refrigerant and lubricant systems, but formulation and duty matter. Obtain OEM or compound-supplier evidence for the exact refrigerant, oil, additives, temperature cycle and decompression conditions.

No family-wide compatibility claim

PTFE

PTFE products can be screened for selected refrigerant-side joints. Creep, recovery, permeation, filler, cold flow, flange stress, surface finish, bolt load and pressure-temperature cycling still determine whether the construction is suitable.

Joint design remains essential

Silicone

Selected solid and cellular silicone products can suit panel, filter-frame and door seals. Grade, reinforcement, cell structure, tear strength, compression, cleaning exposure and hygiene requirements must match the equipment specification.

Check the exact grade and form

Metallic Gasket Constructions

Spiral wound, kammprofile and ring-type constructions serve different flange systems. Select from the piping design, flange standard, facing, material compatibility, gasket dimensions, bolt load and pressure-temperature duty. Do not substitute one construction from refrigerant name alone.

Flange and gasket data must agree
Compliance

Standards and Regulatory Framework

Current catalogue publication, legal adoption, project edition and the edition attached to equipment approval or a test report are separate records. Confirm the controlling record for each joint.

AS/NZS 5149.1–4:2016

The four-part safety and environmental series for refrigerating systems and heat pumps. Identify the applicable part, system boundary, edition and project requirements rather than treating the series as a gasket approval.

AS/NZS 60335.2.40:2025

This is the audit-date current catalogue publication for relevant electrical heat pumps, air-conditioners and dehumidifiers. The edition adopted in law, named by the equipment approval, specified by the project or used for testing may differ and must be recorded separately.

AS 1668.2:2024

Covers mechanical ventilation in buildings, including outdoor-air and contaminant-control provisions. It does not prescribe a universal duct-gasket material or prove installed leakage performance.

SMACNA Seal Classes

A seal class states which duct joints, seams and penetrations are sealed. Confirm the cited SMACNA publication, duct pressure and leakage class, accepted sealing method and installed test separately.

AS/NZS 4020:2018, Amendment 1:2022

Relevant only where the exact product contacts drinking water within the applicable installation boundary. Evidence must cover the supplied product and intended contact conditions.

Australian HFC Controls

Australia's bulk-HFC quota reduces to 15% of baseline from 2036. The 1 July 2025 equipment rule has a defined manufacture/import scope, charge threshold, GWP threshold and exemptions; it is not a blanket refrigerant installation or service ban.

National Construction Code

Confirm the edition and amendments adopted by the project jurisdiction. Publication of NCC 2025 does not by itself determine the legally applicable edition for a project.

ASHRAE Standard 15-2024

A refrigeration-system safety standard where adopted or specified, with applicable published addenda checked for the project. Its scope excludes ammonia R-717 systems, which require the applicable ammonia pathway.

ASME B16.5-2025

Covers specified pipe flanges and flanged fittings. The piping class, flange material, size, rating, facing and bolting inform joint selection; the standard does not give a loose gasket its own pressure-class rating.

Quoting an HVAC or Refrigeration Joint?

Send the controlled drawing or equipment model, exact fluid and lubricant, pressure-temperature cycle, joint details and document list. We will confirm the product and evidence boundary before quotation.

  • Air-side enquiries include duct construction, seal or leakage class and installed test
  • Refrigerant-side enquiries include OEM source, compound and decompression duty
  • Availability, documentation and any approval route confirmed in writing

Disclaimer

This page is provided for general engineering reference only and does not constitute professional advice, specification, or guarantee of performance. Actual results depend on specific application conditions. Universal Gaskets Pty Ltd accepts no responsibility or liability for decisions made based on this information. For full terms, see our Terms & Conditions.

Temperature ranges, chemical resistance ratings, and mechanical properties cited on this page are typical values for standard grades. Actual performance varies with compound formulation, filler package, and service conditions — contact us to confirm suitability for your specific application.