How to Use a Car Radiator for a Solar Water Heater

How to Use a Car Radiator for a Solar Water Heater
Written By
Eli Laurens
Eli Laurens
Published: Aug 3, 2010
Updated: Nov 20, 2021
1 minute read

Step 1

Gently tamp the radiator's heat fins with the hammer or mallet, so that they lay flat and close the gaps between them. In normal use, these fins would cool the water as it passed through the rows of tubes inside. All of the fins must be pounded flat, front and back.

Step 2

Spray the radiator with black paint, completely covering both sides, and allow it to dry. Several coats may be required for total coverage.

Step 3

Attach the radiator's inlet and output openings to the house's plumbing system using the universal radiator hose and the hose clamps. Tighten the hose clamps with the screwdriver by turning the screw clockwise. The pipes for the home will be close to the same size as the hoses coming from the radiator, and adapters are available should the hose clamps not close tightly enough.

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Step 4

Mount the radiator in a location where is in direct sunlight. As the water passes through the radiator's lines, the black metal structure will heat up, trapping the radiant heat and transferring it to the water.

Tips

Several radiators can be connected in series to increase water temperature and volume.

Warnings

Use extreme caution when moving or repairing the radiator solar heater; the metal and water can be very hot.

Photo Credits

Hemera Technologies/PhotoObjects.net/Getty Images

Eli Laurens

Eli Laurens is a ninth-grade physics teacher as well as a computer programmer and writer. He studied electrical engineering and architecture at Southern Polytechnic University in Marietta, Ga., and now lives in Colorado.

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