Freezer to Refrigerator Conversion
Contents
Video
Video mentions the refrigerator conversion - video from Open Source PV System
Introduction
Convert a freezer to a refrigerator, and reduce energy consumption 12x so that your refrigerator uses 8 Watts of average power.
This translates to about 50 million megawatt hours of electricity (126M households with 1 fridge) saved per year in the USA if everyone converted to an energy saving fridge from a 1kWhr/day scenario today. This is about $5 billion dollars saved per year in America.
Nearly every household on Earth has a verticaldoor fridge that uses 100W of power on average - or about 2.4 kWh per day. In a country of a few million households, replacing vertical door refrigerators with chestfridges can save enough energy to allow closing down at least one large power station. Alternatively, construction of a new power station to meet the increasing energy demand could be avoided or delayed. http://mtbest.net/chest_fridge.html
In money terms, the Superfridge costs 2 cents per day to run (assuming 10 cent per kWh electricity cost). This is about $7 per year - compared to $88 for an average fridge.
For the Seed Eco-Home, the cost is actually even better. The off-grid energy system cost $3000 for 3kW not including labor. This translates to 2 cents per kWh energy cost over a 20 year life of the PV system. That is about $1.50 electricity cost to run the refrigerator for a whole year!
Original Work
This work is based on the Mt_Best_Freezer_to_Refrigerator_Conversion.
Wiring Diagram
Wiring Harness
BOM
Hint: Transition to Arduino Nano, which is less expensive and appears not to get compilation errors like the Sparkfun Pro Micro
Bill of Materials' lists all parts required to build a machine.
amazon
- Sparkfun Pro Micro 3V amazon
- or adafruit Trinket amazon
- Relay amazon
- Themister amazon $4.32
- 10K resistor amazon
- Female Headers amazon
- Jumper Wires M/M amazon
- USB Wall Charger 1A 5V amazon
- 6" USB Cable amazon
- 4"x4"x2" Electrical Junction Box amazon amazon
- 1-11/16 Hole Saw amazon
- Extension Cord amazon
- 2 Conductor Wire amazon
- Crimp Connection Assortment amazon amazon
sparkfun
- Sparkfun Pro Micro 3V - $19.95 sparkfun - Install Instructions
- Arduino MKR1000 WIFI sparkfun
- 24-280VAC Relay - $9.95sparkfun
- or SainSmart Relay Module $3.99 - Requires 5V Board
- Thermister $0.75
- 10k Resistor $0.95
- Female Headers
- Jumper Wires M/M
- USB 5V Charger $3.95
- USB Micro Cable $1.95
- Junction Box $7.23
- Extension Cord - Ace Hardware
- 2 Conductor Speaker Wire - Ace Hardware
- Crimp Connections
Luxury Edition
- 120V Male Receptical amazon
- 120V Female Receptical amazon
- Hole Saw 1-11/16" amazon
- MKR1000 amazon
- Illuminated Plug Extension Cord amazon
- 6x6x4 Junction Box amazon
- potentiometer adafruit grainger
Tools
- step drill bit amazon
- drill
- butt connector crimper amazon
- small blade screw driver
- phillips head screw driver
- soldering iron - for adding headers amazon
- solder amazon
- electrical tape ace
Arduino Code
Hint: Sparkfun Pro Micro controller appears to require Arduino IDE v1.0.1. Not. See installation notes at https://learn.sparkfun.com/tutorials/pro-micro--fio-v3-hookup-guide/installing-mac--linux
Hint: The trigger values below did not work. See Talk:Freezer to Refrigerator Conversion. Try 300 and 310
Code history - File:Fridge code.ini
//A1 read voltage //D3 sensor power //D14 relay (-) volatile int sensorvalue = 328; //define the variable int triggeron = 328; //number that will trigger fridge on int triggeroff = 304; //number that will trigger fridge off // the setup function only runs once every time the chip is reset void setup() { digitalWrite(3, HIGH); //for powering thermister digitalWrite(14, HIGH); //for switching relay pinMode(3, OUTPUT); //begin operating pin pinMode(14, OUTPUT); //begin operating pin delay(20000); // wait for thermister to get a good initial reading } // the loop function runs over and over again forever void loop() { sensorvalue = analogRead(A1); //read sensor if (sensorvalue > triggeron){ //if sensor reads over triggeron, turn on digitalWrite(14, LOW); //turn on relay delay(8000); //wait 8 seconds } if (triggeroff > sensorvalue){ //if sensor reads below triggeroff, turn off digitalWrite(14, HIGH); //turn off relay delay(8000); //wait 8 seconds } }
- See Talk:Freezer to Refrigerator Conversion for explination of trigger values.
Refrigerator + Compressor
- 7.4 LRA on the label. See definition of LRA
- Info about the panasonic compressor: [1], PDF -[2]
- Replacement part on ebay: [3]
- This is the fridge we got (it cost $450): [4]
- This is the closest (in terms of size and price) currently available: [5]
- Best Buy has a 10 cu ft for $270 and 14 cu ft for $370: [6]
- Sam's club has 10 cu ft for $240: [7]
- Notes on how a Refrigerator Compressor works
Other Options
- http://mikeysklar.blogspot.com/p/yatc.html
- https://www.amazon.com/gp/product/B0002EAL58
- https://johnlvs2run.wordpress.com/2009/10/08/chest-fridge-conversion/