herms tesco kettle

tazuk · Nov 20, 2012

well its about time i got it built at last to say i made coil then long time ago viewtopic.php?f=13&t=26183&p=250166&hilit=herms+kettle#p250166
so thought i would try solder some joints up fist time ever done lol

also get me new baby too

just need some think to fit each end of kettle to hold the coil in place ?????

Kevin Wood · Nov 21, 2012

Ahh! Very similar to the one I've just made, copied here:

The coil measures 85mm diameter by about 135mm height.

Here it is installed in the kettle. Coil sits on a non-heating part of the element and just reaches the "max fill" level.

After removing the scale filter mesh you can close the lid.

Tubes are connected using straight Yorkshire solder joints to provide a "barb" and secured with automotive fuel line clips.

I started off with a 10m roll of pipe and I've got 5.5m left, so about 4.5m used.

I'd be interested to know if the solar pump is man enough to get decent flow through such a tight coil of pipe.

Andyhull · Nov 21, 2012

How does that work then?
Is the kettle on a stat to come in and out at a specified temprature to hold the mash temp?

Kevin Wood · Nov 21, 2012

Andyhull said:
How does that work then?
Is the kettle on a stat to come in and out at a specified temprature to hold the mash temp?

Yes, pretty much. I use a PID to control the kettle element, with the temperature probe in the flow from the coil back into the mash. The PID therefore maintains a constant temperature of wort returning to the mash by varying the heat that's applied to the kettle.

In practice I've found that the water in the kettle settles at about 72 degrees C to maintain the mash at 66 degrees, although that would depend on the amount of heat that's lost from the mash tun and the efficiency of the heat exchanger in the kettle.