This unit operates on a 120VAC 60Hz input

scorch marks

the part is likely failing and requires replacement

One-pipe steam systems require a specialized air vent valve to function correctly

Fenwal 12-F27121-000-10 Mounting Head 326058-758 This unit operates on aThe Fenwal 12 F27121 000 10 Mounting Head is a high precision, vertical mount Detect A Fire thermal detector engineered for critical fire suppression and alarm circuits. Rated for 275 degrees F, this rate compensated detector utilizes a unique V Fast response time index to ensure rapid activation during fast growth fire events while effectively ignoring transient thermal gradients that cause false alarms in standard rate of rise units. The 300