I bought a house last year that has forced air heat but no A/C. It does however, have a well. I'm in MN where the annual temperature average is 40-45, therefore so is the groundwater. In the past I've heard a lot about home made well water powered cooling. Farmers running water through an old truck radiator with a fan behind it, etc. Strangely though I can find little to no info about such projects on the net.
Anyways, I got my hands on the 4-4.5 ton evap coil seen in the picture below (cased). I plan to install this on top of my upflow furnace and run water through it at whatever rate needed to about maintain geo temp. The liquid line is of course the bottle neck, but in this size coil it's 3/8" which should be good.
Now, here's the question. I think my furnace is a two speed, and I could just set the thermostat to FAN: ON (which will be the lower speed, I assume) and run downstairs and turn the water on until my house is cold. But I don't seem like the kind of guy that would be happy with that, do I? Rather, I'd like to wire in a 24v solenoid valve to the PCB on my furnace so I can set the temp on my thermostat, so the water goes on, and the fan goes on high, when it's time to cool.
As shown in the pictures, there's only three wires running from the thermostat to my furnace and I understand I need to run another for from the Y post to the Y post on the furnace PCB.
Then were do can I hook up the solenoid?
I see this forum discourages DIYers doing standard HVAC projects, but hey this is not a project for a HVAC profession so hopefully this isn't inappropriate here. Any help would be much appreciated.