Can Coleman-Mach Signature Mach 3 RV Air Conditioner System Install on 1 inch Thick Roof
Updated 10/21/2026 | Published 10/20/2026
Question:
I am converting a 1996 WandW 3-horse slant gooseneck horse trailer into a camper and am considering the CM58RR. My trailer already has a reinforced 14x14 roof opening. The roof assembly is approximately 1inch thick, and the opening is reinforced with existing steel support beams. Before purchasing the unit, I need to confirm: 1. Is the CM58RR compatible with a roof assembly approximately 1inch thick? 2. What is the minimum and maximum permitted roof thickness for this model? 3. Does the unit require a particular mounting frame, spacer, or bolt arrangement for a steel roof? 4. Is the existing 14x14 opening acceptable, or does this model require a 14 1/4 x 14 1/4 opening? 5. Are there any any special mounting requirements for a steel horse trailer that will experience road vibration? Id appreciate the the installation manual and any model-specific mounting guidance you can provide.
asked by: Ryan B
Expert Reply:
Hey Ryan, these are all really great questions I would love to help you with. A 1 inch thick roof will work great with the Coleman Mach # CM58RR as that is the minimum thickness that Coleman says is okay with this unit. They do not show a maximum thickness figure.
For steel roof installs Coleman recommends their spring pad kit part # 8333-3871 which isn't something we carry at this time.
A 14 inch square opening is perfectly fine to use with this.
There isn't anything extra required since this is a horse trailer.
I am working on getting the install instructions link added to the product page.
Product Page this Question was Asked From
Coleman-Mach Signature Mach 3 RV Air Conditioner System - 13,500 Btu - Non-Ducted - R32
- RV Air Conditioners
- Complete AC System
- Cool Only
- 13500 Btu
- Standard Height
- Single Zone
- Rooftop
- Non-Ducted
- White
- Coleman-Mach
more information >
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Ryan B.
10/21/2026
Thanks for the information. I have two final questions before ordering the Coleman Mach Signature Mach 3, model CM58RR. 1. Does this specific model come with a factory-installed soft-start system, such as the Micro-Air EasyStart, or would I need to purchase and install one separately? 2. Since I’m installing this unit on a steel-roof horse trailer conversion, is the Coleman spring pad kit, part 8333-3871, mandatory? If so, can you recommend a source for obtaining it? I’m trying to ensure the unit will operate reliably on a generator and that my steel-roof installation meets the manufacturer’s requirements.