Air not so tite

[kwired]

If thermal insulation is causing light to cycle on and off you either have too large of a lamp or a non insulated ceiling rated fixture.

Add to that defective thermal protector, stuff happens.

i didnt take the offending overload out and analyze it, i just moved the insulation away and problem solved. i think we all know a can lite always says @65W max. okay, well never say always, but i put all the lights in this house in, and light bulbs. i can bet you the overload was made in china. land of the utmost in quality control

All the fixtures I can recall the max lamp size is not determined soley by the can, it is usually a combination of whether the can is an IC or non IC can, type of trim, and type of lamp that determines max lamp size. You can usually use a larger reflector type lamp than you can use a type 'A' lamp, the reflector lamp radiates more heat downward than regular lamps.

Prescolite cans I used to use were identical between the IC and non IC cans except for the thermal protector - I'm fairly sure the temperature setting of the protector was the only difference.

 

[kbsparky]

Just get some of that spray foam insulation and seal `er up on the outside of the can from the attic. Quick and cheap.

 

[Nium]

Add to that defective thermal protector, stuff happens.

Truth be told I've never come across a failed thermal protector. When I first started out I did use to think they'd fail till I tryed to locate replacements at local supply houses. In my experience no one carries replacements and from what I figure it's because they don't fail and I eventually figured out the problem wasn't the thermal protector. They are just a simple bi-metallic strip configuration device not a whole lot in there to go bad. If the lamp's cycling then I'd figure to much insulation covering non-IC recessed fixture or lamp to large and lamp wattages aren't always 60W the trim IIRC typically dictates lamp wattage.

I would be interested if someone has actually replaced a thermal protector due to a proven failure of the device and not just a supposition.

 

[kwired]

Truth be told I've never come across a failed thermal protector. When I first started out I did use to think they'd fail till I tryed to locate replacements at local supply houses. In my experience no one carries replacements and from what I figure it's because they don't fail and I eventually figured out the problem wasn't the thermal protector. They are just a simple bi-metallic strip configuration device not a whole lot in there to go bad. If the lamp's cycling then I'd figure to much insulation covering non-IC recessed fixture or lamp to large and lamp wattages aren't always 60W the trim IIRC typically dictates lamp wattage.

I would be interested if someone has actually replaced a thermal protector due to a proven failure of the device and not just a supposition.

Only failure I ever recall was not electrical failure, but the stupid mounting clips like to break off. Find them that way sometimes fresh from the box while installing. Suppliers will replace them but it is still unproductive time spent dealing with that.

 

[Dennis Alwon]

I have literally install thousands of Halo cans in my career and have never replaced a can because of TP failure. In fact I have only had to replace a couple due to bad sockets-- What else can go bad-- trims well yeah I have replace them for one reason or another.

 

[S'mise]

I've replaced them because one of the tabs broke off that hold the shower trim in place.

Does anyone see a problem with spray foaming the top of the can? I know they are ic rated but is that alowed?

 

[cadpoint]

....
Does anyone see a problem with spray foaming the top of the can? I know they are ic rated but is that alowed?

To be honest, I don't see why you didn't take the suggestion to lay a bead of chaulk on the underside of orginal light!

For all that's worth... JMO

 

[Dennis Alwon]

I've replaced them because one of the tabs broke off that hold the shower trim in place.

Does anyone see a problem with spray foaming the top of the can? I know they are ic rated but is that alowed?

I see a big problem with it esp. when it is done and the only access to the box is from the can. That JB is suppose to be accessible but it can't be when buried in foam.

 

[S'mise]

Cadpoint; It is leaking from the inside portion around the lamp (Even with the furnace not running). A bead of caulk would do nothing.

Dennis, I would not cover the jbox with foam, just the can portion. It sounds easier than boxing in each can.

If the draft is noticable from one can, I can only imagine how much heat is escaping through a dozen of them.

 

[cadpoint]

Ain't the first, it won't be the last time that I missed it! But here is what your dealing with.

energystar.gov

Not in this article but I read somewhere else that the average house has the equaliviant of 3 sq feet worth of openings in there house, or leak equilvilant.
As earlier mentioned I beleive you need to understand your whole house and all the symptoms to properly address and attack your problem.

I've also read else where were modern houses say the 90's on are so air tight that by design there is no make up air and that this strains the conventional forced air systems, but that would be another thread and forum!

 

[S'mise]

solution to drafty cans

solution to drafty cans

Thought I'd share what i did to solve the leaks. I used round styrofoam minnow buckets to cover the top of the cans (but not the j-box) and spray-foamed around the bottom.

Worked perfectly. I have about 3" of clearance inside the bucket to the can, so It would probably be OK with non IC cans too. Thanks everyone for your advice.

 

[hurk27]

A couple of responses, A forced air heating system or air handler, will not try to bring in outside air unless it is blowing inside air out,
yes a gas fired water heater, furnace fire places will all try to bring in make up air if not enough supply is available, but that is about it,
now if you have more return air that the supply can deliver to a room you will create a negative pressure and outside air will try to make up the difference, if you have too small a return compared to the supply you will create a positive pressure, and it will try to escape to the outside, if you have an equalizing gap under the door it will try to return or supply this path first, this is why it is always good to have a gap under your doors, all it wants to do is get back to the blower that moved it, kind of like a transformer with current.

Now wind putting a positive pressure on one side of a building will force air into a structure if air can flow out the other side, now theres something we have to seal out.

 

[muskrat]

But what about bath fans, range hoods, etc, all exhausting to outside w/ no make-up-air. (Commercial jobs require it)

 

[LarryFine]

A couple of responses, A forced air heating system or air handler, will not try to bring in outside air unless it is blowing inside air out,
yes a gas fired water heater, furnace fire places will all try to bring in make up air if not enough supply is available, but that is about it,

A house has a lot of equipment that moves inside air out: fuel-fired furnaces, water heaters, etc., kitchen and bath exhausts, clothes dryer, etc., but nothing to pre-condition the air that replaces it.

I've often thought of running an exterior air-intake duct into the return on our forced-air furnace, so fresh air enters and mixes with the conditioned air, rather than entering through doors and windows.

I haven't done it, but I've thought about it. It's got to make the space more comfortable, and commercial buildings do it. I think positive indoor pressure would be better than negative indoor pressure.


Added: I see I'm not the only one who thinks about that. It's probably better for complete exhausting of combustion gasses, too.

 

[iwire]

http://www.smarthome.com/3033/HE150-Air-to-Air-Heat-Exchanger/p.aspx

 

[LarryFine]

http://www.smarthome.com/3033/HE150-Air-to-Air-Heat-Exchanger/p.aspx

That's for fresh-air exchange in well-sealed buildings while minimizing heat gain or loss, but doesn't make up (pardon the pun) for one-way air removal.

I'd rather have fresh air pre-conditioned and mixed with interior air than brought in raw through exterior penetrations where I feel it on me directly.

The new air must be cooled or heated anyway, but I would think it would be more comfortable with it mixed with existing interior air before it hits us.

 

[muskrat]

That's for fresh-air exchange in well-sealed buildings while minimizing heat gain or loss, but doesn't make up (pardon the pun) for one-way air removal.

I'd rather have fresh air pre-conditioned and mixed with interior air than brought in raw through exterior penetrations where I feel it on me directly.

The new air must be cooled or heated anyway, but I would think it would be more comfortable with it mixed with existing interior air before it hits us.

I've seen that (prefered)as well as piped to near floor in unused but heated living space i.e. mech. room