I am trying to understand a simple hot water urn and need to know how it works electrically and what certain buttons do. I found an instruction manual here and just trying to figure out different models and whether they are doing the same thing:
http://www.confettipartyrentals.com/galleryupload/webdoc/guides/Instruction%20Manual%20-%20Water%20Boiler.pdfThis one has a BOILING/OFF button and KEEP WARM/OFF button:
This one has a ON/OFF button and YOM TOV/OFF button, and 2 lights (HEATING and WARM):
I am guessing that these water heater urns are identical except for the labelling. The BOILING/OFF button is equivalent to the ON/OFF button. The KEEP WARM/OFF button is equivalent to the YOM TOV/OFF button (which is a Jewish Sabbath version as per the above manual).
My understanding is that the BOILING/OFF and ON/OFF buttons turn on the water heater element to the full current and it will keep going until the water in the tank is boiled, and it will keep boiling until all of the water is completely gone? It never shuts off? Do you have to monitor the tank and see or hear that it is boiling and then shut it off manually by turning the switch off again? Or is there a thermostat that will automatically pop the boiling button off again?
The KEEP WARM/OFF or YOM TOV/OFF button sounds like it puts a small amount of current through the (same?) element but not enough to boil the water... Just enough to keep it heating to compensate for the heat loss of the tank.
What happens when you switch on BOTH switches? Wouldn't the BOIL button over-ride the KEEP WARM if it never shuts off? Why wouldn't they use a 3-way switch... BOIL/OFF/KEEP WARM..... The Boil setting puts the full current through the element in the tank. Then after it is boiled, you flip it over to KEEP WARM and it will put a smaller current through to keep heating the water.
Or I would design it with a BOIL switch that "pops" out after it has boiled the tank, like electric tea kettles which stop boiling the water. Then have a "KEEP WARM" toggle switch that lets you decide whether or not you want to keep running a smaller current through the element for keeping things warm after you've boiled the tank.
I'm sure it is simple but never having owned one and looking at different models I am trying to grasp what is going on with these things, and internally how they are wired up. Thanks!