Heat Exchanger Question

[liammckenna]

It is my understanding that iodophor needs to be in the acidic range to work and that anyuthing over ph 7 has virtually no antimicrobial effect. Have used products containing phosphoric and nitric acids as acidifiers. Found that extended soak of fittings sometimes led to corrosion.

Determined that it was usually due to the brewers failing to actually measure solution, instead, 'eyeballing' it until it looked right. In some cases it was also due to 'cheap' or lower quality (read cheap) stainless fittings.

Could not support iodophor in a 'blind' situation like heat exchanger. I normally just use heat (in the form of very hot water) immediately prior to use (after of course regular cleaning cycles). If I had to leave HE soaking, I'd think about Sparkle Brite/ Diversol to fill it. It is a TSP-based mixed halogen (chlorine/bromine), should be not corrosive to stainless in proper concentration, wear gloves, however. Pretty corrosive to your hands.

Pax.

[Buckley]

I have always just ran a CIP cycle of caustic, hot rinse then acid leaving the acid in the system until the next cleaning and brew cycle. We have yet to have a problem with that.

[Jephro]

I have always just ran a CIP cycle of caustic, hot rinse then acid leaving the acid in the system until the next cleaning and brew cycle. We have yet to have a problem with that.

Just what i have always done.

[danielbholmes]

What do you think about leaving caustic or acid in the H/E for long periods of time?

[Buckley]

I would imagine that all are CIP-ing prior to brewing anyways, so for long term storage water/dry really wouldn't matter since your HE should be clean after the brew day is done.

[RobZamites]

I don't think leaving caustic in for a long time would be great, OTOH, I think packing with acid for a long-term downtime would be okay, as long as the HX was thoroughly caustic'd/rinsed before hand.

[Sir Brewsalot]

I've been packing mine with hot PBW solution (5-Star's Caustic Substitute) for the last 2 years, only to be followed by a very hot water rinse on brew day to heat sanitize... reading all this, you've got me wondering if I need to passivate the stainless on my plate and frame.

Never had the thing appart, but I noticed a few months into this practice that my knockout times got a bit shorter.

Think I need to run some acid through there?

Cheers,
Scott

[Jephro]

Caustic ?

I have been told that caustic can corrode stainless if it remains in contact over long periods of time....Is this true??
jeff

[aswissbrewer]

caustic or sanitiser?

After CIP I used to leave my heat exchanger packed with 1.5% caustic solution over longer periods of time. After dismantling it on one or two occasions to remove the hop residues that I sucked into it I didn't notice any corrosion.

Just the same, I decided to switch to sanitiser as I didn't trust the killing effect of the caustic - especially with all that plant matter in there. I switched to packing with sanitiser. I use formalin 0.3-0.5%, strong stuff with no corrosion problems. I rinse with hot water before sending the next wort through.

[dick murton]

Caustic won't cause corrosion of stainless steel, but it might cause deterioration of the gasket rubbers or glue if you use glued in place gaskets. The key to cleaning PHEs is high speed CIP, and with hot wort heat exchangers backward flow at at least forward flow design rate, often 1.5 times. If you are using whole hops, you really need a coarse mesh filter to trap the triffids coming out of the whirlpool / hopback.

If your times are extending, consider acid descaling the water side of the PHE. If you have any temporary hardness in the water, it will fur up just like a domestic kettle and restrict water flow and heat exchange. Warm to medium hot nitric acid is best for this. Don't use hydrochloric acid. Sulphuric acid will of course form insoluble CaSO4, a real pig to shift, phosphoric will form an insoluble calcium phosphate layer - also a pig to shift.


Re formalin - in the UK at least, this is considered carcinogenic, we are not allowed to use it, although I have used it with superb results in the dim & distant past. Check if you are permitted to use it before going further. Also it is not pleasant stuff to work with.

Cheers

[Stephen]

Opening HE?

How often are people taking apart their HEs? I've been back-flushing CIP caustic then acid after every brew, then heat rinsing the day of. After a couple of years (no one told me otherwise, being new to the profession), I started having some off flavors and even bad beer. I took apart the HE and found one ugly mess. Should the HE be taken apart regularly? Taking into consideration the amount of brewing down per week/month/year.

[Sulfur]

Cooler Sanitation

An alternative to formalin (i.e.formaldehyde) as a standing sanitizer is Glutaraldehyde Also, as to the cold water side, I have a theory that letting it rise to no higher than 75 deg C will prevent scale from building up on that side - scale forms above 75 deg C. The rest you can cool with your coolant.

[cfelix_123]

it is useful:
caustic sol. 1-2% for 30 minutes / 80ºC and
nitric acid, 1% for 15 minutes.

[JoeV]

embalm the heat exchanger?

I don't think I would recomend using formalin or glut. in the cold water side or beer contact side of anything in the brewery. No I know where the stories of beer coming from other countries (other than USA) has formalin in it. So yeah I would just keep the stuff out of the brewery.