Copper Thermostat Bulb

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Is it safe to place your copper thermostat bulb directly into your wort while brewing. If so what is the best method for doing this?

My thought was to bypass the airlock and go for glab wrap with the bulb insterted.

Currently my bulb sits in a 2 little bottle of water that helps stablize the temp (no sudden fluctuations when the door is open). However during the first few days of fermentation the wort temp is a few degree warmer. I usally compensate by setting the temp lower. the exact variation however varies from brew to brew.

As you can see in the pic I need to build a stronger bottom shelf and remove the frezzer.



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Personally I wouldn't go dangling the copper bulb in the wort.

1. It's a PITA to sterilise and I don't like things dangling in the wort. The fewer the better IMO

2. The capillary on copper bulbs isn't really flexible enough to be putting it in and out of the wort. I'd be worried about kinking it or breaking it rendering your thermostat as stuffed. The less you move these capillaries about the better.

I think if you wanted a more accurate measure of fermentation temp:

1. Tape the bulb to the outside of the fermenter, this would be accurate enough in my books.

2. If you wanted a more accurate measure of fermentation temp, make a neoprene, Armaflex (pipe insulation) or some sort of foam belt (say around 10cm wide) to wrap around the fermenter. Then insert your bulb under the belt between belt and fermenter. The insulation will warm to the temp of the fermenter while insulating the bulb from the air temp outside.

That would be the way I'd tackle it. Hope it helps.

Cheers, Justin


Just a Hoe
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I'd go with Justin's idea, sounds very feasible. In fact I might even do it to. :super:

Usually I just compensate and set my thermostat a couple of degrees lower. So if I want to ferment at say 16c, I just assume a water temp of 12-13c to be near enough to what I want. Not 100% accurate but it seems to work well enough.

BTW Cubbie those shelves can and "do" break. I had four kegs make the shelf give way once and one managed to slam down on my foot. :eek:

Thankfully I had a pair of steel-capped Blundstones on at the time. A plastic fermenter could result in a big mess.

Make a wooden shelf. It's quite easy.

Warren -

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