Fermentation fridge problem

[glove81]

Excuse me if wrong forum.

My fermentation chamber (an 18 month old fridge) isn't working right. If I switch it off at the wall and leave it for a while it will kick in fine and bring the temp down. Problem is it won't ever kick back in again unless I do the same shut down and wait thing.

Any ideas what may be wrong? Only just noticed as I'm cold crashing, up to now it has recently been under low demand as it was fermenting around air temp so can't be sure how long or what has happened.

 

[Buffers brewery]

What temperature controller are you using? Does it indicate 'cooling' but fridge doesn't run?

 

[glove81]

Inkbird.

I disconnected the fridge from the controller and plugged it directly to the mains. The inkbird is currently just monitoring the temp not controlling the setup.

I've used a Thermopen and an Arduino based thermometer to verify it isn't a dodgy inkbird read.

 

[Buffers brewery]

If I understand it, your fridge is plugged directly to the mains and it’s thermostat is turned to ‘max’ and your inkbird is monitoring temperature, not controlling. When you turn the fridge ON at the mains the fridge runs and chills but when it reaches temperature (3 degrees?) the fridge thermostat turns it off, the temperature rises but the fridge thermostat doesn’t turn the fridge back ON. Is that the situation?

 

[glove81]

Essentially yes. Didn't get as low as 6 before cutting off today.

 

[Buffers brewery]

Did you able to confirm that it was the fridge thermostat that switched OFF? i.e. did you turn the thermostat knob and it didn't 'click'?

 

[glove81]

Not sure I'm fully getting you there.

Right now the fridge has power and the dial is set to 5 but the temp is rising.

Do you mean I should turn the dial down and listen for a click?

 

[Buffers brewery]

Sometimes, electric motors are fitted with thermal cut-outs to prevent motors over-heating and causing fires. Don't know if fridge pumps are fitted with such devices but in my former life the company I worked for made vacuum pumps and in order to comply with the required standards (CE mark ) the motors had to have a thermal cut-out. If the motor has stopped prematurely (6 degrees doesn't sound like max) the thermostat will still be in the ON mode unless you turn it down (temperature up) at which point it'll turn OFF at the MIN setting.....I think

 

[glove81]

There was no click when I turned it down just now. Yesterday when it was cooling I turned the thermostat down to try and get some idea of what was happening, it worked by stopping the compressor ( I assume) as it went quiet. I have turned the fridge off at the dial and will unplug and leave it for a while before starting all over again. Fridge repair guy up here not keen to come to it as it was just a cheap fridge from currys. I hate the thought of it going to the dump when it is little over a year old.

 

[Buffers brewery]

So, sounds like the thermostat is working as it turned OFF yesterday when you turned it down. It didn't click ON today when it should've as the temperature was high so the problem (in my opinion) is with the pump circuit not the thermostat. Sorry, that's about as far as I can go on this one as I've never taken a fridge apart

 

[glove81]

So, sounds like the thermostat is working as it turned OFF yesterday when you turned it down. It didn't click ON today when it should've as the temperature was high so the problem (in my opinion) is with the pump circuit not the thermostat. Sorry, that's about as far as I can go on this one as I've never taken a fridge apart

Appreciate the help. Once I've bottled this batch I'll get in about it.

 

[glove81]

So, sounds like the thermostat is working as it turned OFF yesterday when you turned it down. It didn't click ON today when it should've as the temperature was high so the problem (in my opinion) is with the pump circuit not the thermostat. Sorry, that's about as far as I can go on this one as I've never taken a fridge apart

Appreciate the help. Once I've bottled this batch I'll get in about it.