Temperature Dynamics

[Hopeye]

Hi,

I have a temp. controlled (lol) fermentation box that I built sometime ago and I have recently noticed an odd thing happening. Over the past three days I have been recording the temp inside the box and outside the box and have noticed that when I replace the cooling elements (four 2litre bottles of frozen water) of the heat exchange unit of the box I will get upto 3 degrees temperature drop inside the box (from 14c to 11c) in the morning and early afternoon, But, when I replace the cooling elements in the late afternoon / evening I only get a half of a degree drop inside the box. Has anyone else with a home built fermentation box noticed this strange occurence ??? I have replaced the bottles of ice at @ 7:00am and 1:00pm and 7:00pm. I get temperature drops of 3 degrees at 7am & 1pm, but, only a half a degree drop at 7pm.

Strange.

Beers,

 

[timmy]

how cold are the bottles that go in? Are they all the same temp?

 

[Hopeye]

The shed (detached brick 2 car garage) is on the north side of the house. The cooling elements are four 2 litre PET bottles of frozen water having been frozen for the past 24 hours. I have 12 bottles that I rotate in use every 24 hours or so. I just found it strange as I would've thought that as the box is on castors (there is air space all around the box) that I would have had the same chilling efficiency regardless of the time of day....

Beers,

 

[RobW]

Have you measured the shed temps? Pretty sure you'll get decreased efficiency if the ambient temp is higher, which it will be by afternoon/evening. Conversely when the shed is colder in the morning, your system will be more efficient.

 

[PistolPatch]

So Hopeye, your 7pm bottles are cooling for 12 hours whilst the other two are only cooling for 6. I'm wondering, how long after you place the ice blocks in are you doing your temperature check?

I am not getting the same as you so it certainly is weird unless you are only checking the 7pm result 12 hours later. If so, then all would be a little less strange. Cheers mate!