I’m closing the business after a great 13 years.
I will continue to offer support and honor the
and do any repairs as needed.
I have a few products still in inventory
and then they are all gone!
Thanks to you all!
Guy Marsden

Solar Powered Differential Temperature Controllers

GaiaMoto Alternative

Improves the efficiency of solar heating systems!

Designed to control solar powered pumps in closed loop solar heating systems,  these differential temperature controllers will improve performance by preventing a solar powered pump from running if the collectors become cooler than the storage tank.  This typically occurs on overcast days and early and late on cold days when there is enough sunlight on the solar panel to power the pump, but the collectors are not hotter than the storage tank.

The principal advantage of an off grid solar heating system is reliability. A system that uses AC powered circulation pumps is at the mercy of the utility rather than a solar panel. If the grid fails on a sunny day causing your pump to stop, you can cook the antifreeze in the collectors and risk a chemical cascade failure which turns the antifreeze acidic. This can then rot your copper plumbing and cause an expensive system failure.

We are committed to a sustainable way of life for the planet. Our products are fully warranted and made in America.

“This is a terrific product and I am VERY satisfied. Even for me as a MD it was easy to install.  Good documentation, thank you very much.”more testimonials here.

Reference: Solar Powered Differential Temperature Controllers

DTC-1-Solar Powered Differential Temperature Controller


Basic model. Fixed differential is less than 1 degree F. Simple and affordable.

DTC-AT-Solar Powered Differential Temperature Controller


Adjustable differential from 5 to 32F and max shut down or over temp warning/shut down for storage tank adjustable from 80 to 200F.
DTC-D-Solar Powered Differential Temperature Controller


Many features including audible freeze and high temp alarms, stored max/min temperatures, digital accuracy.

Simple Hookup Diagram

Unit wires in between the solar panel and pump. Sensors are attached to collector pipe, and storage tank wall.

Solar House Heating System Control Diagram

Video Overview of Product Line

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