Is it true that flourescent light bulbs get hot enough to trip heat sensors in new electrical construction ?

What type of trim is on the can? The CFL could be to big for the can and trim combo. Also inside the can are adjustments to raise and lower the socket, try lowering it alittle and see if that helps out. All new recess cans have a termial cut out on top of them to keep them from getting to hot. Last thing to check and see if the cans are IC type cans. IC cans are they only ones that are allowed to have insulation blow on top of them.

The base of the bulb does heat up as that is where the starter or ballast is located but certainly not hot enough to trip the heat sensor in the fixture can. Try a standard incandescent light that is rated for the fixture (40Watt, 60Watt, or whatever) and see if it trips it. If so, get the contractor back - he might have left insulation on top of the cans when he shouldn't have. It is possible it is an installation problem.

I find it hard to believe also as those fluorescent's

draw less power, and convert more of the draw to light than incandescents.

Are these recessed 'cans' installed in contact with insulation?

Are they rated for that ? (Some are not, for this very reason.)

If the fixture is misapplied it could account for a heat build-up.

By your contractor's response it makes me wonder. Did he also provide the recessed cans for you? If he did they might be Halo's. They are junk and cause a lot of people unhappiness. Other wise all the other answers covered all the other possible issues.

I don' t believe what your contractor said. I would check and see what size bulbs you have in the cans, it sounds like you might have the wrong size in them.

That does not make sense to me, since Flourescents are much cooler than regular bulbs.

NO