Heat box update.
I spent a few days building a pre-heater for the big heat box. Some of this was posted earlier – this is the update. The idea was to build a box that would re-heat the air as it flowed through the box. The other box works on a draw idea sort of like a chimney… hot air rises so as the air is drawn in from the bottom and heated, it will exit through the top. Adding a fan to force the air increased the amount of air coming into the shop. The average temperature on a sunny day varied depending on the speed of the fan. For example, low-speed on the fan would shoot anywhere from 70 to 80 degrees into the shop. Turning it to high would shoot something like 65 to 75. A higher volume of air traveling through the box would keep the output cooler.
I hooked things up and went in to read the thermometer. The setting on the fan was high (there’s low, medium and high) and I was getting about 86 degrees. When I was testing this it was morning and it was mostly sunny. There were clouds and clouds do cool down the intensity of the sun on the boxes. I turned the fan to low thinking that the lower force of air would allow the heat to build up even more and I would get a higher reading. Not so. The temp started to drop. When it got down to around 71 I turned the fan once again to high and the temp increased back into the upper 80’s. Not sure what is going on… pretty sure the clouds had something to do with it. I’ll conduct more tests as the sun shines. So far it seems that the addition of the box allows higher heat to come through with a greater amount of air.