Tips on cleaning out a plate chiller?

[Kev888]

I've recently been fortunate enough to get myself a pre-loved plate chiller I can't use it until I sort a better filter out for the boiler, but I thought I'd give it a damn good clean before first use.

I've currently got it sat in a saucepan of boiling water whilst I recirculate hot percarbonate-based cleaner through the wort side of things (in reverse to the normal flow direction). So far I've collected about a tablespoon's worth of tea-leaf sized hop particles and some small white organic looking flecks and the cleaning solution has gone rather brown, so clearly its having a useful effect.

Should I be doing anything else - acid cleaning for minerals for instance? I'm a bit nervous of such things as I believe its braised together with copper..

Cheers
Kev

[testtube]

Hot caustic, thought I had done a good job cleaning mine with hot water and cleaner steriliser until I used hot caustic, the junk that came out! The instructions say to use brupaks caustic stuff antiformin s or something..

[Kev888]

Ah, interesting, many thanks. I flushed it through both ways until stuff stopped coming out, but I guess there's no guarantee that I got it all. I'm going to sanitise it in the pressure cooker before each use, but it'd still be nice to start with it as clean as possible.

Cheers
kev

[testtube]

It was more like stuck on wort rather than bit's, I always looked after it, but came out like stout! Caustic's not brilliant with copper, I admit but....

[Kev888]

Ah yes, thanks; on reflection caustic may be a bit risky, especially as my plate chiller may be several years old for all I know... However, maybe for a first (or occasional) clean its worth it.. I noticed in a thread elsewhere aleman was doing something along those lines too.

I must have mucked up the search before because I didn't find what I wanted, but I also came across this thread. Looks like a careful citric wash may be worthwhile but also that the murphey's alkaline cleaner would be safer than caustic for regular use. From what I can tell, it seems to be different to the percarbonate-based stuff I've been using, so could work in additional ways.

Cheers
Kev

[Aleman]

Caustic's not brilliant with copper, I admit but...

Ah yes, thanks; on reflection caustic may be a bit risky

Copper is fine with hot caustic, Dow do not recomend storing a 50% Caustic Solution in copper tanks, but we are not using anything like that sort of strength (I normally use around 100g in 5 litres). Indeed Halliday describes the anodic behaviour of Copper in a Caustic solution to the effect that the copper eventually becomes passivated with a layer of Cu(OH)2 (Or CuO in a stirred solution).

Any layers of oxide or hydroxide formed are stripped anyway because you always follow a caustic wash with an acidic one. Are you weakening the copper brazing?? Well possibly but then we are running acidic wort through copper pipes (in many of our breweries) but who worries about the pipes corroding??

Looks like a careful citric wash may be worthwhile but also that the murphey's alkaline cleaner would be safer than caustic for regular use. From what I can tell, it seems to be different to the percarbonate-based stuff I've been using, so could work in additional ways.

I don't think Citric acid is 'harsh' enough, I have always used a 1% solution of phosphoric acid . . . and I do think that I might be trying that Murphys Alkaline cleanser myself . . . While Caustic is a great cheap effective cleanser the handling requirements and care required in use tend to put me off using it

[GrowlingDogBeer]

Anyone got this in a idiots guide format.

I'm not too good with chemicals as I really don't understand them, and they scare me a bit as they can be a bit nasty if you get it wrong.

I have put a Plate Chiller,this one http://www.ebay.co.uk/itm/Stainless-Ste ... 4cfbb4e853 , on my Christmas list as I have decided it's a better option than upgrading my Immersion Chiller, I will also be getting one of them Solar Pumps so I can pump into a fermenter.

I don't have a pressure cooker, so do I need to get one of them?

Then in what order do I need to run chemicals through, it looks like I need to run an acid cleaner through, followed by an Alkaline Cleaner, but I'm not really sure.

Another thing that occurs to me is that I only have the standard copper pipe Hop Filter with 1.5mm holes in, this works fine at the moment as by the time I run off the wort I have a nice hop bed creating a filter and I recirculate the first few litres with a jug, however this won't be the case using a plate chiller so presumably I need some form of finer filter to stop any hop seeds or little bits of hop coming out of the boiler. Any tips.

Thanks

[Aleman]

I don't have a pressure cooker, so do I need to get one of them?

No, you can chemically sanitise . . . Or recirculate boiling water for 10-15 minutes

Then in what order do I need to run chemicals through, it looks like I need to run an acid cleaner through, followed by an Alkaline Cleaner, but I'm not really sure.

My Procedure is this

1) back flush the wort side with hot water, until it runs clear
2) Wash with hot alkaline cleaner (both ways) . . .using the pump to recirculate for 10 minutes each way (Washing Soda, PBW, Antiformin, Caustic Soda)
3) Flush with hot water
4) Recirculate an acid solution round it both ways for 10 minutes (Phosphoric Acid, Other acids are available)
5) Flush with hot water, and drain
6) Pressure cook for 20 minutes
7) fill with boiling water and cap with blanking nuts

Before use driain and connect into the system, I normally run the pump for 10 minutes pumping boiling wort round the system before turning the coolant on.

Another thing that occurs to me is that I only have the standard copper pipe Hop Filter with 1.5mm holes in, this works fine at the moment

I use a #30 mesh hop stopper which has a hole size of 0.514mm perhaps a tad to big but fine in my case, when doing my initial back flush I don't get any debris flushed out. . . . You could always put your copper pipe hop filter inside a #30 mesh bag

[GrowlingDogBeer]

Thanks Aleman, thats really helpful.

I have Washing Soda, and Citric Acid (had to buy some to clean out the wifes iron), so they should do the trick.

I'll probably get hold of some #30 mesh as well and use that around my existing hop stopper.

I may persuade the wife she wants a pressure cooker for Christmas too

[Kev888]

Copper is fine with hot caustic, Dow do not recomend storing a 50% Caustic Solution in copper tanks, but we are not using anything like that sort of strength (I normally use around 100g in 5 litres). Indeed Halliday describes the anodic behaviour of Copper in a Caustic solution to the effect that the copper eventually becomes passivated with a layer of Cu(OH)2 (Or CuO in a stirred solution).

Any layers of oxide or hydroxide formed are stripped anyway because you always follow a caustic wash with an acidic one. Are you weakening the copper brazing?? Well possibly but then we are running acidic wort through copper pipes (in many of our breweries) but who worries about the pipes corroding??

I don't think Citric acid is 'harsh' enough, I have always used a 1% solution of phosphoric acid . . . and I do think that I might be trying that Murphys Alkaline cleanser myself . . . While Caustic is a great cheap effective cleanser the handling requirements and care required in use tend to put me off using it

Many thanks for that!! - really very useful to know, and all very reassuring. Think I'll get some caustic for initial/occasional deep cleaning then, but probably I'll try the murpheys cleaner for more general (less hazardous) use.

Steve, I bought a pressure cooker a while ago, aspiring to do slants and stuff, but actually its really useful/quick for all manner of heat-proof bits and bobs. I don't know how it compares, but I also saw that some people boil the plate chiller filled/submerged in a big pan for half an hour or so, or bake in the oven for a couple of hours. I guess in the latter case you'd need to be sure it was clean though, so as not to bake on any residue in the dry heat.

Cheers,
Kev

[Kev888]

Just a small update on this: today I ran very hot caustic soda at about 100g per gallon through the plate chiller for 10mins in each direction (crikey, I'd forgotten how it fizzes up when you mix it!).

It did find a few tiny particles, but it looks very much like the initial, lengthy recirculation of hot percarbonate-based cleaner probably got most of it (this was a home-made mix of 2x sodium percarbonate to 1x sodium metasilicate at 25g per gallon). However, it took my percarbonate mix many hours to stop freeing bits from the chiller, so I'd guess its a trade off between aggressiveness and contact time. Caustic soda may be much more convenient (or at least quicker) day-to-day.

I know this is a 'first clean' and so over and above what I'd be doing normally. But even so, one thing I'll say about this experience (with all the forward/backward recirculating, rinsing and different cleaning/sanitising solutions) is that its probably going encourage me into getting some quicker disconnects..

Perhaps a smaller hopper for the cleaning chemicals too; my tanks are wide and provide too shallow a reservoir without lots of cleaning solution - fairly wasteful if you're recirculating the same stuff anyway. I wonder if one could configure all the brew-day hoses, pumps and so on into a sort of circuit and clean them all in one process..

Cheers
kev

[testtube]

Think I used 10g/litre, not too hot! I then jam a funnel in the out and pour in a few times, give it a little jiggle. Yeah it's vicious stuff.. I think mine's 5/6 years old now, never had any trouble.. Only just started using caustic for it.. A filter is a good idea or slowly blocks up and temp keeps changing, as you might expect..

I flush with main's then boiling water after use, then maybe some caustic/water/boiling water when I've got 5mins sometime, then circulate with VWP or Chemipro Oxy when I use it, and me other gubbins in one circuit like ur thinking..

[Kev888]

Crikey that caustic mix is about 5x the strength I used.. oh well; after hours of hot percarbonate/metasilicate plus the caustic plus all the boiling water (all in each direction) it must be clean 'enough' for my satisfaction now... The steam is a very good idea too though; I'd imagine (if it works) one could attach a wallpaper stripper to the wort port

I did the phosphoric acid flushing this PM, for 10mins in both directions, using 12ml (of 81% solution) per L of water... I hope thats about the right strength anyway; disturbingly, the water went a slight coppery colour, and my brass fittings seem now to look like copper so I guess the zinc may have started dissolving

Think I'll invest in some better marigolds..

Cheers
kev

[testtube]

Think I'll invest in some better marigolds..

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