ozone control for geothermal dehumidifier

[alec_t]

I did not supply 5V to the 4020

Ah, that would make a teenzy-weenzy difference .

It works perfectly with the LED.

Excellent. I can stop tearing my hair out (what's left of it) .

Should we wait until the snubbers are installed to test run the radio (in place of the ozonizer) the variac and blower?

As KISS says, the occasional test run won't harm the relay contacts much; but frequent on/offs will burn them if the snubbers aren't in place.

D1 still shows 1976 or so with the DMM probes reversed.

Measuring D1 in circuit applies a voltage between the IC input pins also. I'm guessing that reading is due to a current path in the IC via its input internal protection diodes. ICs generally don't like voltages (from the DMM on Ohms range) applied to their inputs if their power supply is switched off.

 

[salty joe]

The AC caps arrived so the snubbers are installed and this little beauty of a circuit works exactly as planned. Thank you Alec, I am truly impressed with the way you can manipulate parts to get the desired result. You come up with amazing and creative solutions.

 

[alec_t]

Aw shucks, you're making me blush . Good to know it's doing its thing. Those snubbers will prolong the relay contact life.