A big mistake
I made a big mistake and managed to kill off 3 out of my 4 chilli plants by being a prat.
Everything was setup and working fine, they were growing ok, if a little small.
I put the reduced growth down to a lack of sunlight inside the shed so purchased some better grow lights for the system.
What I had not taken into account was the hot wether we were about to get.
I installed the lights, set them up to run 12 hours a day and patted myself on the back for a job well done.
Two days later we had one of the hottest 2 weeks on record for May.
The new lights along with the sunlight made the shed too hot, the inside of the shed at one point reached 48C or 118F, way too hot for the chillis.
During this loverly warm spell, the watering system carried on doing its job of watering the chillis when the soil moisture dropped below 40%.
As anyone who calls themselves a gardener knows you don’t water plants when its hot.
In effect by not using forward thinking I had setup the perfect conditions to kill my plants, this was a big mistake.
Much better now
In order to correct my error, I fitted a larger 12V blower fan to pull in cool air from behind the shed.
I also lowered the grow light brightness so they were running cooler and updated the code so that the water pump will only come on when the light sensor is reading less than 5, in effect at night.
The sole survivor of my error is a Carolina Reaper plant a friend has named Rambo. He is doing very well now the system has been altered.