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#3 I work for a major appliance
repair company/retailer. Replacing the
factory compressor start device with
an after-market hard start kit is not
recommended. Most of those kits — if
not used or sized correctly — can
cause permanent compressor failure. I
would suggest trying to source the
correct part by model and serial number of the refrigerator. There is a major
appliance parts dealer in Cincinnati
and Dayton that can help. If you can
not find a model or serial, I suggest
Whirlpool part number 8201786. This
kit covers several different compressors, as well as wiring connections.
I can't find the paperwork on the
last MARS device I purchased. Any
local HVAC distributor should be able
to locate what you need, depending
on the compressor size. It's just a two
I'm including a PDF document
from MARS and my refrigeration
document for you to view. Download
them at www.nutsvolts.com in the
[#6126 - June 2012]
I need a simple schematic
diagram which shows how the home
thermostat controller is connected
to the gas heater and to the air
conditioning at the same time.
[#6125 - June 2012]
I’m considering converting an old
car with manual steering to electric.
However, DC motors about 10 HP
or more are expensive. I saw that the
Northern Tool catalog has a 10 kw
generator head with brushless technology (item 165928). Is this a 13 HP
brushless DC motor I could modify?
Here is documentation for a
typical thermostat. Make sure you
know what voltage your existing system uses before making a purchase.
I think the schematic is self-explanatory (Figures 2A and 2B).
Additional documentation can be
found at www.nutsvolts.com in the
#4 The original part is shown at
The three terminals on the device
are C, S, and R. C is connected to the
COMMON of the compressor, with S
being START winding, and R being
I'd suggest replacing the original
device, and adding the proper
MARS hard start device to kick the
compressor. You don't want to bypass
the overload! PERIOD!
MARS Motors & Armatures, Inc.,
has hard start devices and torque multipliers for refrigeration/AC compressors.
I've used a smaller MARS hard start
device on several refrigerators, and they
work fine. ( www.marsm-a.com/CGI-
You can ask the expert at
Northern Tool, but I am sure he will
tell you that this is a single phase, 220
VAC generator and cannot be used
as a motor. A three-phase generator
could possibly be used as a motor, but
60 Hz machines don't like to be run at
other frequencies so variable speed
would be a problem. You would need
a clutch and transmission.
[#6128 - June 2012]
Where can I find a schematic or kit
for a 16 button keypad encoder,
without having to program a PIC?
That's a regular telephone keypad plus
A - D on the right side.
#1 The IC for DTMF encoding is a
TP5089 from National, or a second
source is TCM5089 from Texas
It is available from Jameco
( Jameco.com) as TP5089; their item
It's listed as available from stock
on their website. You can also
download datasheets from them to