To answer your first question, the rotating dial with the increasing size of the dots is the thermostat. The larger the dot, the higher i.e. warmer, the desired room temperature setting is. This does not control how hot the radiator gets, but is merely a switch to determine when the heating elements should be energized based on room temperature. In other words, the radiator is either ON or OFF based on the temperature of the room. You should try setting this to maximum. Even with the heater off, you should be able to here a faint clicking noise as you rotate the thermostat from the extreme min to extreme maximum setting. When you here the click, this means you just passed the temperature the thermostat was currently sensing, and now it engaged the switch to turn on the heater to bring the temperature of the room up to the new desired setting. If you do not here a click, then it's possible that the thermostat is bad.
Most newer models of oil filled radiators also have a pendulum type safety switch. This will turn off the heater if it is no longer in it's upright position in order to prevent a possible fire. It is possible that the linkage for this switch got stuck while you were storing the heater in your closet. You could try gently tilting the heater back and forth a few times to try to free it up.
Depending on how electrically inclined you may be, there are a few more things you can check. If you have access to a multimeter or Ohm meter, you can measure the resistance between the hot and neutral pins of the wall plug from the heater (the two bladed plugs, not including the third rounded grounding plug if so equipped). This must be done with the wattage selector switch and thermostat at the maximum settings. A little quick use of the Ohm's Law formula tells us you should read roughly 9.6 Ohms of resistance for a 1500 W heater running on standard US house voltage of 120VAC. My suspicion is that you will read a very large or infinite amount of resistance, indicating an open circuit in the control circuitry. If you can remove the cover where the selector switches are, you can check for any wires that may have come loose and / or fallen off one of the switches or components. If the thermostat proves to be bad (which can also be verified by connecting an ohm meter in parallel with it while turning the knob to maximum and reading a short and then minimum and reading an open for normal function) you could just jump it out by moving the wire from one side of it and landing it on top of the wire on the other side. This could possibly have a somewhat dangerous result depending on the design and vintage of your heater. Modern oil filled radiators have separate thermal safety switches for each of the three heating elements set at obviously different temperatures.
It is very unlikely that all three of the heating elements would have opened simultaneously, thus rendering your radiator useless. Keep in mind that if you are not electrically inclined (I'm guessing not since your asking this question in the first place) the best thing to do is try my first two suggestions of the pendulum switch and the setting the thermostat to maximum and stopping there. As far as I know you would have a very difficult time obtaining replacement parts for your radiator and most of the components are not user serviceable. Please be careful and remember to unplug the radiator from the wall before opening the panels.
--CH--
Craig, December 2007
