Thursday, November 28, 2013

Fan Controller reloaded II

So here is the continuation of the previous chapter, the saga for a nice product.

Final version:

The eagle eyed among you might notice some small changes. Nothing major.
The ones really paying attention might notice the mistakes: DS18B20 is one wire, not I2C, as is indicated (cosmetics), and the silkscreen for the 12V and the 5V regulators is inverted (cosmetics with high potential for disaster). The soldering holes for the screw connectors could also be a tiny bit bigger, but that depends on the connectors used (could be problematic, as I used some big ones).

I only noticed these mistakes after the boards arrived, luckily before soldering the regulators, so no harm done!

but, following the intense design sessions, I sent it out to be manufactured by Fritzing, and the boards arrived, a bit more than a week later! Great service is all I can say. Here they are in all their glory:

 I really think they came out amazing!

And here in the box, with some components located, not soldered yet:

And finally, in the box, with the components (attiny is missing):

In the third chapter, the completed thing, with screws, micro, lid, everything! and some considerations for improvements.


Bob Basant said...

Hello where can i reach you. I would like to discus the specification of your openterm controler. I would like to use my round honeywell modulation thermostate and your openterm pcb interfaced by internet using 1 jeeNode. Is it possiple to send a new setpoint to the honeywell termostate by your pcb? How can i order the pcb? You can reach me on my email.

Alex said...


I couldn't find your email to answer you back, so here it goes:

With my opentherm PCB it is not possible to send a new setpoint to a thermostat. My implementation completely replaces the thermostat, relying in other sources to determine the desired setpoint.
To send a new setpoint to the thermostat via the opentherm interface, I think you should look into the OpenTherm gateway that someone else did, and I think you can buy PCB's and get support somewhere.
Send me your email, and we can discuss further.