Four Seasons hatches - Are they any good?

Hi Tassi tiger,
Yes, these hatches have a known leak point, I think Kiwijim mentioned it in a thread some time ago, it's nothing that cannot be cured with a small dab of silicon(neutral cure type). you can always clean off the old sealant with a scraper and judicious use of turps then re-seal in a neater manner if you so desire. just be careful how much you pay for a second hand one, the unglazed ones are worth about $360.00 new. I have fitted one to my Franklin a few years back and they are really good. They are one of the few hatches that meet the current gas codes for permanent ventilation.This can be a requirement for registration in some states as the gas code is retrospective for compliance issues.

Frankidownunder.

Your plumbers advice sounds good, I fitted a vent into the bottom of the door as I have no openings in the floor, my fridge is 12 volt only.
The part in the current gas code relating to roof vents is to ensure there is no build up of carbon monoxide inside the van when gas appliances are in use. The 4 seasons hatch meets this requirement even when closed. if you can pick one up at the right price all the better, they are not too hard to fit, the opening in my roof was the same size as the outer edge of the mounting flange so I put an aluminium angle section around the inside of the opening, level with the top, installed an aluminium flashing over the angle and down to the roof then installed the hatch using the "hydraulicing" method of sealing with neutral cure silicon sealant, no leaks there.
The 4 seasons hatch fits an opening of 660 x 660 mm, my roof opening was 710 x 710 mm. so 25mm angle just did the job perfectly. Just say if you need any further advice with your refit.

Frankidownunder.

Give me a few days & I'll get up a sketch of how I did the installation and put it on the site. My hatch was completely different to your one, seems Franklin have kept the same opening though since goodnes knows when.
I fitted an Australite venturi type vent into the lower part of my door, seems to keep the weather and most of the dust out, can get a photo of that installation.
Hydraulicing sealant simply means putting the sealant in between the parts being joined then putting them together,(same way you glue two peices of wood together) thus forcing the excess sealant out. this gives a complete seal that does not deteriorate, unlike a fillet application which only sticks on the outside of the joint. By masking up the area to be sealed then scraping off the excess that extrudes from the joint you can achieve a very neat job, finally clean up the area with turps to remove any final residue before the sealant sets.

This is how I fitted the four seasons hatch to my Franklin van, there are several ways that the job can be done, I chose to use Aluminium angle as it is significantly lighter than wood and as I was working within very tight weight considerations it was my choice.



The above picture shows the new hatch in place before the internal reveal trim was installed. These trims are not cheap and you probably could make up something that looks good out of plywood.



This outside view shows the flashing method that I used, it has the same angle as the closed hatch, the idea is to reduce turbulence around the hatch when the van is in motion. The flashing is sealed and rivited to the roof skin, the original flashings are still in place underneath, so if the outer one leaks the inner one, which only goes up the sides of the support structure and not under the hatch, will prevent water getting into the roof structure.



The above cross section sketch shows details of the method I used.



This photo shows the Australite vent installed in the original door. I removed the small centre door and reduced its height enough to fit the Australite vent in place, At the bottom of the small door, on the inside is an angle forming a sill for the small door to close against and keep water from running under and onto the van floor.

Hope this info is useful to you.

Frankidownunder.

The aluminium 4 season hatch flap falls out when I open it.Real pain as I need to get onto the top of van to put it back into place while someone inside closes it.Has anyone had similar problem.