Bionaire bh3950 heater - tilt sensor reversed? Having problems with my unit. Main power toggle button stuck, so I ordered new on and replaced, switch works better, but still doesn’t power on. Removed front panel and located the safety tilt sensor. When in normal position (when weight bar contacts metal in sensor) no power, but when I manually lift the bar so there is no contact between the bar and the metal contact, power switch lights up and unit heats up fine. I even adjusted the thermostat control and lo/high toggle button on front while I had the tilt sensor manually lifted (in accompanying photo) and all these options worked fine. I’m not an electrical pro, but it seems like the tilt sensor function is reversed. As long as the unit is straight up, the wighted tilt bar sensor makes contact with metal connection on the sensor to complete the circuit and keep it in. If the unit tilts, the sensor bar becomes disconnected to the metal on the sensor and therefore should ‘break’ the circuit and shut off the unit for safety. Am I missing something here? Thank you in advance.

SOURCE: Bionaire BH3950 Does not heat

I'm not an expert, but I have two of these units that are working fine.

The on/off switch (the top switch) has a light in it that illuminates when the heater is on and heating. If this light comes on and there is no heat, then the element is probably burned out.

The heater has a safety switch that prevents the unit from working if it is not upright. If the heater was stored for any length of time on its side, the safety switch might have stuck in the off position. Unplug the heater and with the heater upright, try shaking it or slapping it firmly with your hand to se if this fixes the problem.

If none of this works, then as sunmasc says, the thermostat is bad.

SOURCE: How to reset Tilt Switch in LASKO Ceramic Heater 5540?

I don't have manual, it's a borrowed one. Several days later, I pushed the botton at the bottom several times, looks it solved my problem.

SOURCE: Lift-Master GDO goes up, not down

If the door operates freely without any binding, while operating it manually then It would appear that the obstruction sensor mounted across the doors path is ether out of alignment, lens dirty,or malfunctioning

SOURCE: How do I clean the contact points between kettle and platform?

PROBLEM:

My problem was similar for the Cuisinart KUA-17.  I clicked down the on switch and it stayed down.  However, the light and power together seemed finicky.  That is, the light came on if I positioned the kettle in the base correctly, but then it sometimes went off without triggering the switch to pop up.  When the light went off while the switch remained down the water never boiled, but when I was lucky to position it such that the light remained on, the water did boil and the switch popped up ... as it should have.  It seemed to be getting more and more finicky and difficult to position correctly ... so I took it apart.
SOLUTION:
First of all, the base has screws that take a triangle screwdriver which I don't have.  So I found a small flat-headed screwdriver (like one you'd use for glasses) that just fit along one side of the triangle.  I was able to get three base screws out this way and since I expected to need to do this again in the future, I used my dremel to grind a larger flat-headed screwdriver slot in each.  It's been about a year and a half since I fixed it last time and this time I was glad I had the slots.
Once you get the plastic base off, you'll see the mechanics of the switch.  There are two wires that both turn on the light and power the heater element.  Where the wires connect to the switch mechanism, there are two metal tabs that stick out in opposite directions from the center.  When the switch is pushed down, you can see these two tabs move.  They are each moving to touch a contact and complete the electrical circuit.  My problem was they were not making a good contact.  The contacts are hidden behind the tabs.  All I had to do was bend the contacts one millimeter closer (i.e. as little as possible) so that they would make a good contact.  The only other trick was I had to remove the switch mechanism from the bottom of the kettle to do this.  Then I just used the same small flat-headed screwdriver to bend the contact as in the picture below.

SOURCE: Need photo of Defrost Switch or Sensor

Unit needs to be cold when you test. it closes at around 20 or 30 degrees F and opens around 55 deg F