Modified Trickle Down Solar Heating Collectors

Richard's collectors are entering their third winter season -- this is his report on how they are doing.

Hi Gary,

Have had a few questions on how I plumed the feed lines on my trickle down collectors, below a simple diagram of how I did it. Might answer a few questions.

The collectors are still fully functional. Had to take them down this spring to fix a roof leak under them. I also shortened them by a foot so they didn't stick above the roof line, aesthetics. The felt has gone a tan color but they seem to perform about the same. Don't have the data collection back running, so no hard numbers, but the tank still comes up to about the same temp, even with taking 12 sq. ft. off the area. I tried using supermarket Rite dye to recolor the felt, just dumped 4 packs into the tank. For a couple weeks it looked like it might work. The felt had streaks of black showing, and the rest was turning gray. Then little by little the black just faded away again. Rite dye must degrade in sunlight.

MTD trickle connections

Seeing the first snow of the season in the mountains today finally provided the incentive to write a short update on the steel version of my MTD collectors. Yesterday it was 85 *F and today it is 45*F, and the 145 *F I had in the tank yesterday evening is keeping me warm today. I have found that even with the small 100 Ft^2 set of collectors I am nearly 100% solar heat in the early fall and late spring.

I am going into the third winter with these same collectors. I have done virtually no changes to the design. They are as functional as the day I installed them. Since I made my own differential control for them I have played with the control, but the system remains the same since last year. In fact I left the same water in the system for the entire last year. From looking at the sight glass I have lost only about 25 gallons thru evaporation thru some of the small areas available. I have seen absolutely no indication of algae growing in the water, and have drained a bit to look at it, and it is still clear enough to think you could drink it, NOT!

Over this last summer I left the system running, just as if it were still heating season. I have the tank enclosed in a wood box with two layers of R13 fiberglass to insulate. There is a removable panel on one end of the tank enclosure. I removed the panel for the summer. Left the outside door to the sun room open to vent the heat during the day, and further cool the tank overnight. I noticed that the room just behind the collectors stayed a great deal cooler thru the summer. I believe that running the collector during the day and dumping the heat overnight, helped keep the house a bit cooler, and reduced the load on the evaporative cooler I use. With the high summer sun the water temperatures did not go nearly as high as I would have thought, seldom over 155 *F at the end of the day.

The Mylar (polyester) is still clear and shows no sign of deterioration even after stagnating all last summer and running all this last summer. The gutter seal has shown no sign of leaks at all. It is looking promising that I have found the right combination of materials to have a MTD system with longevity.

Update on Richard's MTD Solar Heating Collectors After 2 Full Years of Service