Originally Posted By: phinsperger This post was automatically imported from our archived forum.
Excessive heat melts a piece of the retaining clip (top center in pic) and releases the metal curtain which slams shut under spring action. This shuts off (or reduces) the supply of oxygen to the burning room. As bob said, found mainly in commercial buildings. Sometimes required in multi dwellings as well.
Originally Posted By: jpeck This post was automatically imported from our archived forum.
Broward County requirement for a/c return air openings in the garage / living space fire rate wall assembly. You should be seeing it all the time in houses before the Florida Building Code.
Originally Posted By: hgordon This post was automatically imported from our archived forum.
A Fire Damper device has been installed at the Return Plenum incorrectly. The device does not provide total draft stopping should the device be engaged. NOTE: This inspection can not acertaing with any certainty the funtionality of the Fire Damper. Consult with a Licensed HVAC Contractor to determine funtionality and or safetiness of this device.
Originally Posted By: jpeck This post was automatically imported from our archived forum.
Bob Badger wrote:
Jerry you guys down there AC the garage?
You folks must have money to burn. 
Up here in the cold it is very rare to find a heated garage.
Bob,
No, the garage is not air conditioned, but the air handler is in the garage on an enclosed return air plenum stand with a return air filter opening to the living space, through the fire rated wall assembly.
Broward County had a fire rated wall assembly separating the garage from the house, Palm Beach County (and the rest of the state, in fact the entire Southeast US under the Standard Building Code) did not.
Miami-Dade county also had the fire rated wall separation between the garage and living spaces.
Originally Posted By: Bob Badger This post was automatically imported from our archived forum.
jpeck wrote:
Bob,
No, the garage is not air conditioned, but the air handler is in the garage on an enclosed return air plenum stand with a return air filter opening to the living space, through the fire rated wall assembly.
Ahhh that makes sense and it is understandable why a fire damper would be needed.
Originally Posted By: hgordon This post was automatically imported from our archived forum.
But hold on guys…the return plenum is (actually “was” prior to the garage being converted) buth the return grill is in the home…so does that change anything?
Originally Posted By: jpeck This post was automatically imported from our archived forum.
Harvey,
When the air handler is installed in the garage and the return air opening is through the wall to the living space, it should have that damper at the return air opening through the fire rated wall assembly.
I write it up as 'missing fire damper at return air penetration through the fire rated wall assembly between the garage and living space'. Note, however, that the new code does not require a fire rated wall assembly separating the garage from the living space and thus does not require a fire damper in the return air opening.
Enforcement started slacking off when the Florida Building Code was being argued about (er ... discussed) and this was being dropped. The lack of enforcement argument was 'why bother with this since the entire fire rated wall assembly was not going to be required anyway?'. A semi-valid argument for non-enforcement of something which will not be required soon.
There were many things going on during those couple of years leading to the code change.
Some inspectors said 'You must do this today because it is required today, even though it will not be required tomorrow.', while other inspectors said 'If this is not going to be required tomorrow, I sure as he&& ain't going to enforce it today.' Both view points have some validity.
If seat belts were not required to be installed in a car made tomorrow, why bother to install them in a car made today?
Apparently 'safety' is not the issue, if it was, it would still be required tomorrow. 
Originally Posted By: jpeck This post was automatically imported from our archived forum.
Harvey,
If the garage was converted WITH A PERMIT, then the fire damper is no longer needed.
No permit and it is still a "garage" and needs to have the fire damper, and a permit, and ... and ... and (because of not being permitted, if not permitted - and most garage conversions are not permitted).
I would not get into all that verbiage, just state that it is not there when needed. Trying to get into something like this too far means your choice of words needs to be precise, for CYA, while a more general 'it ain't there' simply states 'it ain't there', and it can be addressed from that point by the contractor installing it.
Originally Posted By: jpeck This post was automatically imported from our archived forum.
hgordon wrote:
OK Jerry...but in this case it IS there...so again do I CYA by saying it's there but I did not "test it"...or should I say nothing at all?
IT IS THERE, but it DOES NOT NEED TO BE THERE, thus it does not need to work. You can say it is there and you did not test it, but I don't think that is necessary.
Originally Posted By: jpeck This post was automatically imported from our archived forum.
Checking e-mail, however, here are some other points on that a/c return air plenum.
It should not have exposed plywood, it should be insulated and lined with duct board.
That looks like the concrete garage floor was left exposed, as was a common practice until we got all over them about it (concrete is not an approved duct liner), and it also needs to be insulated and lined with duct board.
All edges and openings to the wall framing should be closed off and sealed.
Being as the fire damper is not needed, and IF (the question / statement I keep making) the garage was permitted, I would recommend removal of the fire damper. I found one which 'dropped' and closed off the opening (no wonder the a/c was not cooling properly). No fire, so no one knew what caused it to close, but it was closed.
