Suppose the illustrated self-contained, internal-pilot, piston-operated temperature control valve is part of the temperature control system for a steam-heated heavy fuel oil service heater for a steam boiler. If there was an increase in demand for fuel by the boiler, what statement correctly represents how the valve would initially respond? Illustration GS-0045

Question

Accepted Answer

The fuel oil heater fuel outlet temperature would decrease, causing the remote bulb pressure to decrease and the thermostatic diaphragm to flex upward and through lever action, further open the pilot valve.

Answer

The fuel oil heater fuel outlet temperature would decrease, causing the remote bulb pressure to decrease and the thermostatic diaphragm to flex downward and through lever action, further close the pilot valve.

Answer

The fuel oil heater fuel outlet temperature would increase, causing the remote bulb pressure to increase and the thermostatic diaphragm to flex downward and through lever action, further close the pilot valve.

Answer

The fuel oil heater fuel outlet temperature would increase, causing the remote bulb pressure to increase and the thermostatic diaphragm to flex upward and through lever action, further open the pilot valve.