RV Rooftop A/C Gasket Size Guide: 14×14 vs 14×16 & Mounting Kits

Replacing a compressed roof gasket is not the same as replacing the entire rooftop air conditioner. The seal must match the specific A/C base and its mounting instructions, even when the RV has a common 14 × 14-inch roof opening. Compare the original gasket shape, required size, leveling components and mounting bolts before removing the rooftop unit.

14 × 14 roof opening or 14 × 16 A/C gasket?

Roof openingThis is the hole through the roof into the ceiling assembly, often nominally 14 × 14 inches. It is not always the dimension of the foam gasket mounted beneath the rooftop unit.
Gasket footprintVentmate 65526 is listed as a 14 × 14-inch gasket, while 65527 is a 14 × 16-inch seal configuration for specified Coleman-Mach models. Select the gasket from the actual A/C model, not the ceiling cutout alone.
Mounting hardwareBolts draw the unit down to the specified gasket compression. Roof thickness and model determine whether 8- or 9-inch mounting bolts are appropriate; a gasket kit does not automatically include them.

Roof A/C gasket and mounting parts by exact MPN

The chart separates self-adhesive picture-frame seals, multi-strip replacement seals, model-specific Dometic gaskets and separate bolts. The listed kit contents are not interchangeable merely because the parts share a similar opening size.

MPN Seal / mounting part Manufacturer size reference Included Selection
ACGR-1 Dicor Seal-Tite — Universal-size rooftop A/C gasket kit Manufacturer-described universal replacement gasket Self-adhesive gasket, adhesive leveling blocks and compression guides Compatible rooftop A/C assemblies only after the unit's original seal, roof opening and compression instructions are checked.
3310718.006 Dometic — Rooftop A/C installation gasket 14 × 14 in nominal opening Roof sealing gasket; separate leveling pad not catalogued as included Selected Dometic rooftop A/C bases; model-specific parts list required.
4450037541 Dometic — FreshJet 5 roof gasket kit Approx. 14 × 14 in inside / 17 × 17 in outside Model-specific roof gasket; not the complete mount or fastener set FreshJet 5 model family; verify the complete FJX model code before ordering.
65526 Ventmate — Coleman-Mach square A/C gasket 14 × 14 in gasket configuration Pre-sealed gasket; separate leveling pad not listed Coleman-Mach installations specifying this exact seal size.
65527 Ventmate — Coleman-Mach rectangular A/C gasket 14 × 16 in gasket configuration Pre-sealed gasket; separate leveling pad not listed Coleman-Mach installations calling for a 14 × 16 in gasket, regardless of how the roof opening is described.
25071 Camco — Roof A/C picture-frame gasket and leveling kit 14 × 14 in picture-frame gasket Self-adhesive gasket plus two 1-7/16 × 18 in leveling pads of different thicknesses Compatible roof units requiring a 14 × 14 in gasket and leveling support. Camco says not to apply liquid caulk or silicone with this compression gasket.
A10-1414 Valterra — Four-strip self-adhesive roof A/C seal kit Approx. 14 × 14 in assembled inside / 16 × 16 in outside Four adhesive-backed strips forming the sealing square Compatible roof A/C bases; four-piece strip construction differs from a preformed picture-frame gasket.
8333-3211 Coleman-Mach — 9-inch A/C mounting bolts 9 in length; four bolts Bolt set only; no gasket or leveling pad Match the rooftop unit and roof thickness to the exact required bolt length; never select bolts by gasket size alone.
9108553390 Dometic — 8-inch rooftop A/C mounting-bolt kit Four 1/4-20 × 8 in bolts per supplier specification Mounting bolts only; no roof gasket Selected Dometic rooftops requiring this length and thread; verify manual and original hardware.
Check the original gasket specification: A 14 × 16-inch seal may surround an A/C with a nominal 14 × 14 roof opening. Conversely, a FreshJet 5 unit may require its model-specific Dometic gasket even when the roof hole is a common size. Avoid choosing a “universal” gasket without verifying the A/C maker’s permitted seal and compression requirements.

Before lifting or reinstalling the rooftop air conditioner

  1. Identify the A/C model and service number: Look at the rooftop unit label and its installation manual, not just the ceiling grille or thermostat.
  2. Compare the old seal: Record the gasket shape and dimensions, whether it is a one-piece frame or strip assembly, and where leveling pads are positioned.
  3. Inspect the mounting surface: Check roof condition and any deformation or leak damage. Do not compress the gasket to compensate for an unstable roof.
  4. Use the correct compression method: Follow the manufacturer's sequence and gasket-compression or bolt-torque instructions. Overtightening may cause leakage or roof damage.
  5. Do not improvise sealant: Camco's instructions for the 25071 compression gasket prohibit liquid sealant, silicone and caulking used with that seal. Follow the exact replacement gasket's manual rather than using a generic caulk method.
  6. Manage electrical and lifting hazards: Disconnect required shore/generator/battery supplies and have qualified help lifting and servicing the heavy roof A/C.

Common gasket selection questions

Does Ventmate 65527 automatically fit every 14 × 14-inch rooftop hole? No. Its 14 × 16-inch dimension refers to the specified gasket configuration, not universal compatibility with any unit above a square roof cutout.

What is included with Dicor ACGR-1? Dicor identifies a self-adhesive roof A/C gasket, adhesive-backed leveling blocks and installation compression guides.

Can I use 9-inch Coleman-Mach bolts in place of Dometic's 8-inch bolts? The two bolt kits have different stated lengths and applications. Select only the specific bolt length, thread and quantity required by the original installation instructions.

Shop rooftop A/C gaskets and mounting components

Open the exact part number for product photos and current availability. The first group contains gasket kits; the second group consists of mounting hardware only.

Rooftop air-conditioner sealing gaskets

Separate roof A/C mounting bolts

Related rooftop A/C model diagrams

Before buying installation parts, locate the original model in our Dometic rooftop A/C model directory or consult a relevant Coleman-Mach 15 parts reference. For a newer installation, see the Furrion Chill HE R32 roof-mounting guide. Different generations may require different seals.

Manufacturer source: Dicor Seal-Tite ACGR-1 specification (catalogue PDF). For all other gaskets and bolt kits, use the exact rooftop unit's current manufacturer installation instructions.

Bulletin des pièces de VR

Inscrivez-vous pour nos prochaines promotions !

À propos de NewRVParts

NewRVParts est une boutique en ligne spécialisée dans les pièces et accessoires neufs pour véhicules récréatifs, les équipements pour caravanes portées, les pièces de remorquage et de remorques, les accessoires pour camions et les produits nautiques. Nous servons nos clients partout au Canada et aux États-Unis, en expédiant des produits de fabricants de confiance via un vaste réseau de distribution nord-américain. Magasinez en ligne pour obtenir des pièces de rechange, des équipements et des accessoires livrés directement à votre porte.

Magasiner les pièces de VR