This is the Operation and Maintenance (O&M) manual for CCAT cold box. Please refer to it and keep it up to date with any O&M changes.
Manufacturer: CCAT (Campus Center for Appropriate Technology)
Contact: Address: 1 Harpst St., Arcata, CA 95521,
Tel.: (707) 826-3551,
Email: ccat@humboldt.edu
Model: Cold Box
Category: Natural cooling
Fridge (inches): Height: 6.5’’, Width: 26’’, Depth: 21’’
Volume: 2.05 cf. (cubic feet)
Exterior Dimensions: Height: 49.5’’, Width: 34.5’’, Depth: 27.75’’ Volume: 36 cf. (cubic feet)
Refrigeration: Natural cooling
Warranty: None, Self made
Insulation: Material: Woolen Insulation
Operation
The idea of a cold box is to create a naturally controlled environment that provides short-term housing for fresh fruits and vegetables. The cold box works best if constructed on the northernmost wall of the home or building, this is due to our location in the Northern Hemisphere. It is designed to take in cool air from the outdoors through a vent, allow the air to rise up through the shelves of food, and exit through a top vent. The air that circulates up and through not only is a method of cooling the fruits and vegetables but also removes any of the odors resulting from the ripening process. Insulated walls inside the box maintain it at a cool temperature. This is a simple project that provides an energy efficient solution to a refrigerator as well as offer proper housing for fruits and vegetables which may reduce waste. (Appropedia, CCAT Cold Box, 04/10/2014)
Maintenance
In order to control if the cold box is properly functioning, ambient temperature, room and the temperature inside the fridge have to be measured.
Cooling effectiveness: Measurement conducted on 04/04/2014, 1:30 PM
Room inside temperature: 17.7 C
Outdoor temperature: 16.4 C
Fridge inside temperature: 13.4 C Delta: 3.0 C
Measurements should be repeated and compared to ascertain the overall effectiveness of the CCAT cold box.
Schedule
- Daily
- Avoid keeping the door open if not needed.
- Yearly
- Clean vents of obstructions.
- Check hinges for looseness and rust.
- Check door seals for breaks, tears or incomplete contact between the door and box.
Troubleshooting
Problem | Suggestion |
---|---|
Coldbox is not cooling properly. | Check if vents outside are clogged. |
Coldbox is not cooling properly. | Check if vents are blocked by cooling objects inside the Coldbox. |
No significant cooling measurable. | Avoid keeping the door open if not necessary. Check hinges and seal. |
Suggestions for future changes
- Vent for cool air can be placed lower.
- Data Recording of indoor, outdoor (shade), and cold box interior temperatures for effectiveness analysis.