Thermal Solutions EVO-1000, Installation, Operating And Service Instructions

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A. Description
The microprocessor based temperature controller is utilized for all modulating Thermal Solutions water boilers. The basic
function of the controller is to modulate the firing rate of the burner in response to the boiler heat load. The controller monitors
the boiler water temperature through the use of a sensor located in the boiler pressure vessel. The controller compares the boiler
water temperature to the controller’s user defined operating set-point temperature.
An output signal from the microprocessor varies the blower speed through the use of a variable frequency drive (VFD). The gas
valve regulates an appropriate amount of gas flow for a given air flow or blower speed. The user may adjust the operating set-
point temperature for a given application. In addition, the controller has the ability to change to an alternate set-point through an
external signal for low load conditions (i.e. weekend use, night setback). Outdoor reset is another standard feature, allowing the
boiler operating temperature to vary based on the outdoor ambient temperature. The typical result is a higher seasonal efficiency.
Other features include:
B. Set-Up
All of the control parameters have been set at the factory. There are a few parameters called “Process Parameters” that must be
defined by a qualified operator. The table below will help serve as a reference and record when making adjustments.
Low Fire Hold Multiple Analog Inputs
Multiple Set Points Mod Bus Communications
Digital Inputs Manual Overrive
"AUTO TUNE" Optimization
Parameter Display Value Range* Factory Setting User Setting
Setpoint 1 SP1 145-240 180
Setpoint 2 SP2 145-240 0
Digital Setpoint Shift (optional) dSP 145-240 0
Outside Temperature (optional) TA Consult Factory —
Pre-definition of External
Sepoints (optional)
SP.E Consult Factory —
IX. Temperature Controller Operation for Modulating Boilers
Setpoint Value
Burner On
Decrease Value