## Tuesday, January 23, 2018

### Things keep breaking

I replaced this part about four years ago.

 Can you see the break?
That is why it is handy to have test tools.  You can find things that you cannot see.

The new part is ordered and should show up Wednesday or Thursday.

I seem to have failures when the kids run the dryer.  They run it on the High heat setting.  I don't know why they are in a hurry.  They invariably let it sit over night before attending to the dried clothing.

My belief is that the dryer runs the Low heat setting on 120V and the High setting on 240V.  Power is Amperage .times. Voltage.  Since Amperage is a function of voltage and resistance, the heat is V*V*R V*V/R (correction by sharp-eyed reader, Loren).  That is, doubling the voltage quadruples the heat.

No wonder it always craps out when the kids are running it.

Water Heaters
Mrs ERJ mentioned that the hot water heater seemed to be running at reduced capacity.  The water would go luke warm partway through her shower.

I checked out the water heater while I had the test tool out.  The lower heating element is burned out so I need to replace that as well.

Fortunately the parts are relatively inexpensive.  Heating elements for the dryer run between \$20 and \$40.  Heating elements for the water heater run between \$10 and \$20.

1. And y'all 'need' heated things right now...

2. It's always the lower element when this symptom appears. If the upper burns out there is zero hot water. This is a function of the upper thermostat, which does not allow the lower to work until the upper is satisfied. Upper is never satisfied when upper element burns out.

1. Thanks for reading. And thanks for commenting.

3. Well, watts = V*V/R so theoretically yes, doubling the voltage = 4x the watts of heat/power.
In a normal household that would mean one switch contact moves from the neutral wire to the other 110V leg and then you have 220V going though the device. Haven't actually seen that and the switch pictured doesn't seem to function like that. I haven't taken one apart though. My dryer is solar powered.

1. Thanks for pointing out that I had the formula wrong. Correction made.

The switch that is shown is an over-heat, snap-disc switch. I think it is to protect the system. There is another over-heat switch at the top of the "periscope".

The dryer has a low heat and a high heat cycle. Running the same heating element (there is only one) on 110V or 220V is the cheapest and simplest way to create two levels. I admit to making an assumption based on the evidence.