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Jim Yanik Jim Yanik is offline
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Default Simple Question about Thermal Cutoff (tco) & Fuses

Fred McKenzie wrote in
:

In article

,

j barnes wrote:

Would it be safe for me to replace the 4AMP TCO with a 10amp 152C and
simply add a 4amp fuse immediately before or after the TCO?


JB-

I can't imagine the tea kettle cost much over $30, so it is not cost
effective to buy the exact part. The price appears to be calculated
to encourage you to buy a new samovar instead of repairing yours.

From where did you obtain the specifications for the original part?
What are the samovar's electrical ratings for voltage and power? They
may be on the bottom or next to the electrical wire.

Several coffee makers I checked all use power in the 600 to 800 watt
range. If the samovar operates close to 480 watts (4 Amperes at 120
Volts), you would not want the fuse to blow at 4 Amperes. I suspect
the function of the original part was to protect against a fire when
the pot was operated after all the liquid had boiled away. So the 4
Ampere rating is a maximum operating current, not necessarily the
current at which it blows.

How were you going to install the replacement? Soldering is not a
good idea. Solder could melt under normal operating conditions, and
soldering might damage the TCO if you aren't careful. Crimping is the
better approach, but it is difficult to get a good crimp with solid
wires. Some TCOs come with a "crimping ferrule". It is a small metal
tube (brass?) that you insert two wires into and crimp them together.

Fred


I have a Presto Fry Granddaddy deep fryer that the TCO blew when the
bimetal thermostat contacts welded together. AFAIK,they don't make the
Grandaddy anymore,so I unstuck and filed the contacts,then bought a new TCO
at Radio Shack !! that was a few deg C lower than the original,but same
current rating.It's been working fine ever since. I bought new crimp
ferrules at Skycraft Surplus.(local store,Orlando,FL.!)

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Jim Yanik
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