Cheap Rims Thoughts

[enoch]

Have been thinking about a cheap RIMS chamber using a plastic kettle which remains open at the top. More for doing step mashes rather than RIMS per se.

Would have a 1/2 inch bulkhead fitting near the bottom as an input for wort coming from the MLT via a pump and a 3/4 fitting near the top which would gravity flow back into the top of the MLT.

Would need the larger fitting on the top to make sure the kettle didn't overflow. May make the spout of the kettle hang over edge of MLT to take any runoff.
Your thoughts would be appreciated.

 

[Screwtop]

Have been thinking about a cheap RIMS chamber using a plastic kettle which remains open at the top. More for doing step mashes rather than RIMS per se.

Would have a 1/2 inch bulkhead fitting near the bottom as an input for wort coming from the MLT via a pump and a 3/4 fitting near the top which would gravity flow back into the top of the MLT.

Would need the larger fitting on the top to make sure the kettle didn't overflow. May make the spout of the kettle hang over edge of MLT to take any runoff.
Your thoughts would be appreciated.

Hmm, methinks the pressure would need to be equalised throughout the system by sealing off the top of the kettle so that volume in = volume out otherwise wort may spill out the top. Chamber volume may be too large causing wort to be in contact with the heat source for too long as it would travel too slowly through something so large. But hey, why not try it!

 

[Andyd]

The other thing I've heard people talk about is that you can get some scorching as the wort has direct contact with the element. While some caramelisation is desirable sometimes, I'd prefer to have more control over when it's being introduced.

That's why people generally go for a heat exchange system shortly after deciding to bit the bullet and start investigating RIMS (myself included).

Andy

 

[ant]

I kinda agree with Andyd - if you had it come through a coil at the top of the secondary chamber and back out top of same coil, it could be a HERMS; and without direct heating of wort (although close to temp diferentials if you used a copper coil), it should be close in terms of time required for step mashing without potential for scorching?

 

[enoch]

Balancing the pressure wasn't concerning me much as I was aiming to make the outflow big enough to take the pump flow rate without issue, also it would be above the level of the mlt as obviously there would be issues otherwise.
I run a 70 litre electric boiler with 2x2400W elements without any scorching issues (that I can taste) so I'm happy to take that chance.

 

[Andyd]

Yeah - I don't think the pressure is the issue.

I'd definitely be looking at dumping a copper coil in there - nice and simple, no scorching.

Check out the treads in here about building a HERMS recently posted. There is some discussion about how big vessel to use and how much pipe.

Andy

 

[Sammus]

Another consideration is overheating bits of your mash, with an element you have a high amount of local heating, so you can have bits of your mash really hot - dunno what this would do to the enzyme thing, thought it could be an issue. I recently built a herms for about $15 from a 5L bucket and a few meters of 1/2" copper pipe I had lying around and a kettle element (dont have to use Belle by the way, every cheap kettle I looked at had identical looking elements). I guess I also had a PID temp controller lying around, but with the HERMS setup your directly heating water which in turn heats your mash water, if you put your temp sensor/probe on the outlet part of the coil you can be pretty sure your mash temp isnt fluctuating.

 

[Andyd]

Yep - burning mash is exactly what I was talking about.

On the cheap kettle front, is it just me or is the super cheap chinese market meaning that fewer kettles are being made so that we can reuse their elements (most of them seem to be cordless, and removing the elements is just painful, let alone trying to seal them into a vessel...)


Andy

 

[Sammus]

Yep - burning mash is exactly what I was talking about.

On the cheap kettle front, is it just me or is the super cheap chinese market meaning that fewer kettles are being made so that we can reuse their elements (most of them seem to be cordless, and removing the elements is just painful, let alone trying to seal them into a vessel...)
Andy

The cordless ones are the same, well in GoLo and the reject shop they have heaps and heaps of cordless kettles, and the elements on them look the same again - its just the base of the kettle has 3 slots that the prongs on the back of the element slot into. You only need any old computer psu cord to attach it to the wall.

 

[roger mellie]

Balancing the pressure wasn't concerning me much as I was aiming to make the outflow big enough to take the pump flow rate without issue, also it would be above the level of the mlt as obviously there would be issues otherwise.
I run a 70 litre electric boiler with 2x2400W elements without any scorching issues (that I can taste) so I'm happy to take that chance.

Surely the scorching issues would be related to the amount of flow past the elements - and the retention - which no matter how big the outlet pipe on the top is - is governed by the amount of flow in - which is limited by how fast you can pump out of your mash tun - which is a function of how good your FB is.

The only way I could see this working is to limit the volume in the kettle so that you get a low retention time next to the element.

Just my 2c - I am considering something similar with a heat exchanger I robbed out of a dishwasher.

RM