Heat Controller Water Source Heat Pump manual 2.0WHP Controller Overview, 2.1How It Works

WattMaster WHP Section 4

2.0WHP Controller Overview

2.1How It Works

2.1.1Initialization

On system powerup the COMM LED remains extinguished for five seconds. After this delay, the COMM LED will blink out the address of the controller (Address Switch Setting). The COMM LED will then extinguish for another five seconds and then begin to blink for a twenty second startup delay. At the conclusion of this twenty second period, the COMM LED will begin blinking a diagnostic code every ten seconds. This code is described later in this document. The duration of a powerup initialization sequence is roughly one minute.

During this initialization period, the controller retrieves all operating setpoints from its non-volatile EEPROM memory and initializes all outputs to an OFF condition.

Note: All future references to the Water Source Heat Pump Controller in this docu- ment use WHP as the designation.

2.1.2Operating Summary

At all times, after the conclusion of the initialization sequence, the WHP performs a specific set of operating instructions in the following order: (a - g repeat continuously)

a.Read Analog Inputs for Temperatures and Overrides.

b.Check the RS-485 communications port for any new setpoints from the System Manager and keeps the status updated for the System Manager.

c.If the push-button override is active, it checks the timer to see if the override is finished.

d.Calculates the current occupied/unoccupied mode from its internal week sched- uling.

e.Calculates what state the output relays and analog output should be set to.

f.Updates the diagnostic COMM LED blinking.

g.Stores data in the internal trend log if ready for another log.

4-4 Start-Up and Troubleshooting