What is the device call that shuts down a boiler if the dampen warmth get too illustrious? ...

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Answers:    Boiler fittings:
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Safety valve: used to relieve pressure and prevent possible explosion of a boiler
Water rank indicators: to show the operator the rank of fluid in the boiler, a hose down gauge or dampen column is provided
Bottom blowdown valves
Surface blowdown rank
Circulating pump
Feedwater check valve or clack stopcock: a nonreturn stop valve surrounded by the feedwater line

Steam accoutrements:
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Main steam stop valve
Steam traps
Main steam stop/Check stopcock used on multiple boiler installations

Combustion accessories:
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Fuel grease system
Gas system
Coal system
Automatic combustion systems

Other essential items:
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Pressure gauges
Feed pumps
Fusible plug
Inspectors theory test pressure gauge attachment
Name plate
Registration plate

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It's call a temperature high-limit controller (with almanac reset), sometimes called high-limit aquastat.

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