50L thermopot temperature drop

[keith1664]

I've just about got my 50L thermopot converted and I'm planning a brewday for monday (if I can tie the kids up somewhere). Previously I've filled my coolbox mushtun up with hot water in the bath to preheat it, but I'm thinking thats not going to be so practical now. There seem to be plenty of you out there with the same mashtun, so if I'm not preheating roughly how much temperature will I lose when I fill the tun with hot water?

 

[homebrewstu]

5 minute blast with a hairdryer perhaps. its probably a silly suggestion but at least you will be putting some heat in to the vessel

 

[Tony]

I bring mine into the kitchen the night before to warm up then just before grain time, I pour in a kettle of boiling water. Leave for a couple of minutes and drain.

 

[pjbiker]

I reckon you lose about 10degrees on the transfer but you will have to just try it and keep records. If you know what your strike temperature should be, heat your liquor to 10 degrees higher or more before transferring. You can always cool down with some cold liquor before doughing in.

 

[markp]

..... I pour in a kettle of boiling water. Leave for a couple of minutes and drain.

Me too

 

[graysalchemy]

10 degrees sounds about right. I had a lot of problems in winter I ended up having to pump steam through to get it upto temp in the mash as it dropped more than I had anticipated. Put your grains somewhere warm to keep them at room temp and pre heat the mash tun with a kettle of boiling water cover with lid and leave for 5 mins or so.

:

 

[Hawks]

..... I pour in a kettle of boiling water. Leave for a couple of minutes and drain.

Me too

And me :thumb:

 

[46.philh]

+1 for kettle and about a 10c drop from strike water but is getting warmer outside now.

Some time put some tin foil on top of grist after mashing in but keeps it temperature well anyway especially in this warm weather.

 

[Mark1964]

we have a 32 litre thermobox and we fill from the bottom through the tap ie pvc pipe from hlt tap straight to mash tun tap we generally lose 10 deg c so we heat mash liquor to about 78 deg c by the time the mash tuns filled with water its usually just right :thumb:

 

[keith1664]

What I ended up doing was heating my strike water to 81 degrees, transferring it into the thermopot, i then left it for 5 minutes and then dropped it down to strike temp with a couple of litres of cold water. So 10 degrees is a touch high at this time of year, trouble is it'll be slightly different everytime, so note keeping seems the best way to go.8

 

[Mark1964]

If you add grain to the mash tun 1st then add water from the bottom you will find the temp is near enough the same every time.

 

[keith1664]

Yeah, silicone tubing is on the list of brewery upgrades.
Trouble is it's a long list!

 

[pjbiker]

I ended up having to pump steam through to get it upto temp in the mash as it dropped more than I had anticipated. :

What did you use to pump steam through the mash?

 

[keith1664]

Just in case anyone comes across this thread in the future with the same question.

Ambient temp 9 deg C
25L of water at 81.5 into mash tun.
8 minutes later the water was at 78.4, after 18 minutes 77.

So 3-4 degrees, less than I thought.