Totally new to the Arduiono community and really need help on a project I’m working on.
I’m making a hotbox, which is basically a set of 3 heatlamps, and a fan, which are wired into a 2 way module that regulates the heat. (The link to the original author is in the code!)

I’ve so far been able to find code online to do what i need to a point. so far the box is able to regulate heat between 80°C and 75°C. Trouble is i need it to reset right down to around 30°C and start again after one hour of regulating, so that would then be one full cycle.

please see the code below!

#include <LCD.h>

#include <OneWire.h>

#include <DallasTemperature.h>
Arduino Temperature Controller

YouTube channel: Ardutronix - YouTube

Made by Daedalus

#include <Wire.h>
#include <DallasTemperature.h>
#include <LiquidCrystal_I2C.h>
#define RELAY1 4 // Relay heating
#define RELAY2 6 // Relay cooling

int red = 8; // red LED heating
int blue = 2; // blue LED cooling

#define BACKLIGHT_PIN 13
#define ONE_WIRE_BUS 7
LiquidCrystal_I2C lcd(0x27, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE);
OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature sensors(&oneWire);

void setup() {

pinMode(red, OUTPUT);
pinMode(blue, OUTPUT);
pinMode(RELAY1, OUTPUT);
pinMode(RELAY2, OUTPUT);


void loop() {
lcd.setCursor(0, 0);
lcd.print(" TEMP CONTROL");

float temperature = sensors.getTempCByIndex(0);
lcd.setCursor(0, 2);
lcd.print(" “);

if(temperature < 75)

lcd.setCursor(0, 3);
lcd.print(" Heating");

else if(temperature > 80)

lcd.setCursor(0, 4);
lcd.print(" Cooling ");
lcd.setCursor(0, 3);


Thank you and Please help!

Hello barftaid,

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Thank you.

Please explain the problem in more detail.

You want it to get to a temperature between 75 and 80 and maintain that for an hour? At the end of the hour what happens? It stops maintaining the temp? Does it ever start heating again? If so when?


There is no timing in your code, how does Arduino know when 1 hour has elapsed?
Code a 1 hour millis() timer, when it expires, set your temperature set point down to say, 28 ON to 32 OFF.

Hi, Sorry if it's a bit vague.

At the moment, all the arduino does is regulate between 75 & 80°C. However I need it to cut the lights, and cool the box down to say ~25°C, then start again.

I can then work out how long this all takes in real time, and calculate a cycle, which can give me reliable testing results against targets.

Hi, Sorry if it's a bit vague.

At the moment, all the arduino does is regulate between 75 & 80°C. However I need it to cut the lights, and cool the box down to say ~25°C, then start again.

I can then work out how long this all takes in real time, and calculate a cycle, which can give me reliable testing results against targets.

Still vague. "start again"... by itself, or by command? Immediately, or after some delay? What is the "this" that takes time?

a cycle is the box reaching between 80°C & 75°C, maintaining the temp for 1 hour, then the fan will cool the box down to ~25°C for 1 hour.

Just some background information, the box's purpose is to bake a sample material, then cool it down, and heat it up, then cool it down, etc, etc. this is so that i can see if severe temperatures have any effect on the sample material that is being tested.

my code at the moment, is only able to heat the box up to 80, and maintain between 75 and 80. however i also need the box to cool down to see what effect being subject do constant temperature changes have on the material.

is this a bit clearer for you all to understand? if not please let me know, I appreciate all your expertise.