Thermador 464 ceiling heater . I need a part for this bathroom heater

clean ceiling and use BIN primer (2 coats). Ceiling peeled from build of moisture, install a vent fan and have it wired to bathroom light. This way if light is on fan is on.

Possible wired neg to pos and pos to negative.

check the circut breakers too.

Most likely the problem is a leaking drain pipe in the wall, perhaps because of a failed joint. The reason it's not going down the wall to the floor of the dining room is because there is a top plate on the wall. Most likely the water is running down the bathroom wall, then out over the dining room drywall ceiling. It is finding the lowest spot in the area to accumulate and is soaking into the drywall. Since it is drain water, it is dirty and is picking up additional contaminates from the wall and causing the brown stain. It may or may not be soft, depending on how much water accumulates at one time, but it is slowly breaking down the ceiling where the stain is.
That said, are you sure it's a leak, or are you assuming that since you see the stain on the ceiling. I say this because mice, like many other rodents, usually pick one location to use as their bathroom. If you have mice in the ceiling and this is where they do their thing, you will get the same type of indication.

This is my first thought. Do you have GFI in you house.
I lost power on my front porch one time, found out it was the GFI in my bathroom tripped. Reset it and everything was good. Nothing wrong with the GFI it was my kids playing with it.

Right now a single switch turns on both light and fan.
You want to put in a double switch to control light and fan separately.

But the problem is there is not a separate wire to each the light and fan.
You need a separate wire to each, but the circuit wasn't wired that way.
Usually when the circuit is wired for separate control, there is a red wire that also goes to ceiling box.

Unless you run another wire to the ceiling box, it won't be possible to control light and fan separately.

Electrician can do this pretty easily if there is attic space above bathroom.

Amazon.com: bathroom ceiling heater Broan Product Detail

If you have the old Thermador ceiling type of heater that must be mounted on the ceiling surface there aren't many choices. Only the Broan-Nutone 154 & 157 models. The 154 @ $37 didn't seem to last too long but it's 1/3 the price of the radiant 157 model at about $100+ dollars. The radiant model may last longer

remove the switch and test it with a meter on ohms or remove the switch and disconnect the fan wires and connect the fan wires to an extention cord to test.
Phil

Sounds like your current heat source is not an option (I assume you don't have the option of coming from underneath). I'm thinking electric. Maybe baseboard (depends on space). Be sure it's ground fault protected though!

The vent fan must be exhausted into the outside air via a 4 inch flex duct, this may be difficult if installed in the wall!

You'll be able to access the motor to service it and the wiring junction box from inside the bathroom. Please rate this answer if it was at all helpful.