No power to Heat outlet

Hello fellow brewers!

I built a fermentation chamber using the exact components outlined by FuzzeWuzze on Homebrewtalk:

Raspberry Pi B
Arduino Uno
Sainsmart 2 channel
DS18B20 Sensors

I’ve brewed two brews with no issues, but last week my “heat” outlet stopped functioning.

I’ve verified that the heater is good by plugging it into a dedicated socket.

The Brewpi site (heating for 3hrs…) and SSR (click and red LED) both indicate that the heater should be running, but I am not getting any voltage to the outlet.

As a test, I hooked up a light to the heat outlet and patiently waited for “heating” to engage only to see the light flick on for a second when the SSR clicked and immediately extinguish.

I can see all of my devices on the BrewPi site:

Chamber Temp / Beer Temp (Pin A4)
Chamber Heat (Pin 5)
Chamber Cooler (Pin 6)

I don’t see any indication in my logs that would lead me to believe there is a problem.

*The cooling is functioning normally

Any ideas?

If the LED on the relay board (which is not an SSR but a mechanical relay I think) is ON, then the Arduino or the software is not the problem.

Because I don’t sell the hardware you use, I cannot comment further on where the problem lies. If you disconnect the AC from the mechanical relay, you should be able to measure the switch closing. With an SSR, this is not possible, because it only switches on an AC zero crossing.


You’re correct, it is mechanical not solid state.

I ordered a new Sainsmart 2 channel relay.

Once I get it soldered in I’ll report back.

New Sainsmart 2 channel relay is installed and we’re back in business!

Photo shows garage light being powered on the “heat” side of the outlet.