View Single Post
  #7   Report Post  
Posted to sci.electronics.repair
Electromotive Guru
 
Posts: n/a
Default Dishwasher heating element.

You can often get to the electrical connections by removing the
kick-panel below the door. Check for voltage at the heater terminals.
If there is no voltage, Kill the breaker and open up the door itself
from the inside and check for a burned-away wire, and check for
continuity of the switch in the proper mode, which should connect the
heater to the line. if no continuity exists at the right time as you
turn the knob, the switch itself has burned contacts.

You can either disassemble the switch and burnish them clean, or buy a
new washer as a new timer switch usually costs $250 or more (actual
worth: $4.95) because you were smart enough to find the real
problem...Burnish with a fine non-mica nail file. Upon opening the
switch, the burns from a toasted contact will be obvious if that's
the problem causing it....A 1337 fix to this is to use a relay to
handle the current of the drying element instead of the
ridiculously-overpriced switch, or better, an SCR circuit.
Properly-done, you will make a dishwasher that might actually outlast
the motor or the cavity...

Heated drying is somewhat wasteful, just leave the dishes in there for
the next day. There's no real need to get the dishes into the cupboard
like some kind of national emergency, only to sit for the next 4 days
until they are needed again. If your water heater is set for 145ºF,
then you don't need heated drying unless you are in some kind of
hurry.

Sanitized-drying is nothing more than a fictitious selling-point for
the gullible, as your dishwashing detergent and the heat
automatically-sanitize everything due to the sodium-chloride content.
This goes into the same category as "Amps of power" or
"powerful [x]-amp motor, or any reference to volts or amps as a
unit of power, as well as any usage of the phrase "protecting
your family" or any derivative or variant thereof).

0 ohms means continuity exists, the elements never short, only burn
open, so both elements are good, they are simply not getting power.
find out why and you will have fixed the problem. In all-too-many
cases I have found a wire connection burned away because the next
higher wire gauge, to prevent a potentially-unsafe condition and
increase reliability, would increase manufacturing costs up to 12
cents more per unit. This is most common in american-made appliances
and part of an intentionally-overlooked weakness to add additional
revenue for repair costs in the hopes you will take it back to an
"authorized service center" for repair.

Replace any conductors you may find broken with 14AWG wire instead of
the 16-18AWG that they consider safe for handling a 15-amp circuit. I
have done many conversions on appliances to make them actually safe to
use, as well as reliable and efficient, and never heard a complaint
about the unit again.

As a side note, there is no such thing as an american-made
"energy-efficient" appliance as you may have been often
lead to believe. A dishwasher should draw no more than 2 amps peak
aside from the heater element ("energy-saver"). a washing
machine should not require more than 5, and a dryer motor should not
need any more than 4 amps not counting the heater element (fluff
mode), for any of these to be considered anywhere near
energy-efficient. When in the market, force the salesman to show you
actual motor current.

This is why I never see a truly-japanese-made appliance in the trash
for any other reason than blatant abuse/neglect/otherwise
unwanted-but-functional, yet I see nearly-new american appliances
headed for the trash daily with problems that should never have
happened if anyone cared about quality.