Serially Interfaced Central Heating Programmer

Overview

The project aims to build a central heating programmer based on Microchip PIC16F628A microcontroller in order to control the domestic heating system.

Explanation

A domestic heating boiler was incorporated with this programmer as it provides outputs via two relays to control the supply of hot water and heating. Ten program entries are available wherein the heating and water can be controlled by each one independently. The manual advance of the heating and water is allowed by this programmer while the program control can be disabled in the absence of a user for a few days leaving the water and heating OFF. A normal front panel switch control of the heating and water is also provided while featuring a serial interface that allows a PC running a Terminal Emulator to remotely operate the device.

The hardware of the programmers contains the two relays that switch the mains power to control the boiler. To allow connection into a CAT5 cabling system, it employs an RJ45 socket that take the power, serial data and relay control input signals to the second unit, the programmer unit. A 2x16 line LCD display is located in the programmer front panel.