TECH ST-85, User Manual

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ST- 85 – USER'S MANUAL
I. Description
The ST–85 temperature regulator is intended for use with central heating
boilers. The regulator is used for controlling the central heating water
circulation pump, hot consumption water pump and blow (fan).
The ST-85 is a PID-basedcontroller using a continuous signal . In this
type of controllers, the fan power is calculated based on boiler temperature
and flue gas temperature measured at the boiler outlet. The fan runs
continuously and its power depends directly on the measured boiler
temperature and flue gas temperature as well as the difference between the
two parameters and their setpoint values. Advantages of zPID regulators
include their ability to maintain a stable setpoint temperature without
unnecessary overregulations and oscillations.
By fitting the controller with a flue gas outlet sensor, you can save
from a few up to several percent of fuel, and ensure a steady water
temperature for a longer service life of your heat exchanger (boiler). Flue gas
outlet temperature monitoring ensures reduced harmful dust and gas
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C.H. Pump
H.C.W. Pump
Manual Mode
Encoder knob
Blow
Exit
Standby