Sterlco Royal Series Compact Temperature Control Unit - Manual (Page 27)

Royal Series Water Temperature Control Units Page 27
4 Identifying Controls and Features
4-1 Identifying Mechanical Controls and Features
To and From Process Probes
Two (2) 1,000-ohm (1 K
Ω) platinum RTD probes are included
with your Royal temperature control unit. One is located
downstream from the heater to sense To Process temperature; the
other probe is located upstream from the pump to sense From
Process temperature.
Safety Thermostat
The safety thermostat mounted on the side of the heater tank
protects against thermal runaway. The thermostat guards against
the unlikely event of “runaway” heating. If overheating occurs, the
safety thermostat shuts down heater outputs. The unit continues to
pump water through the system to prevent heater damage. Sterling
recommends that you install an audible or visual alarm to the
terminals provided. Factory installed alarms are available; see the
electrical schematics in your Installation Packet for more
information.
Pressure Relief Valve
If the combined pressure of the cooling supply water and pump
discharge exceeds 150 psig (1,034.25 kPa/10.34 bars), the pressure
relief valve opens and relieves the pressure. This is a non-
adjustable ASME construction valve with a stainless steel spring.
Important!
Route a pipe from the pressure relief valve
to a suitable drain to reduce potential scalding hazard.
The drain line must not have any restrictions or back pressure.