System PartsQuestion 21 of 60
On many air brake vehicles, what is the purpose of the safety relief valve on the first air tank?
a.To warn the driver of low pressure
b.To automatically drain water
c.To protect the tank from too much pressure
d.To apply the spring brakes
Explanation
A safety relief valve protects the air tank and the rest of the system from an unsafe buildup of pressure. It is usually set to open at about 150 psi if the governor fails to cut out the compressor. If it releases air, it signals a problem that a mechanic should fix.
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