Dark spots in Spike Stainless HLT

[4_Sons_Brewing]

I’ve taken a hiatus from brewing (about a year and a half off) and when I looked at my Spike Trio HLT I found some dark spots in the bottom of my kettle. I got most of it off, but still some spots or staining in the bottom of the kettle (see pic). This is my HLT so it may have been some residual water with brewing salts left in it, but it may have just had a little water left in it that evaporated over time. I generally give everything a good cleaning vacuum out any residual water and then leave them to dry, but as mentioned I may have left a bit of water in the kettle. tried a PBW scrub, a PBW soak and scrub, and a Bar Keepers Friend scrub. Any thoughts or suggestions on what else to try?

 

[Bobby_M]

That's a bit of rust. It's time for 3 gallons of water mixed with 1 pound of citric acid, heat and hold at 150F for 2 hours. Then rinse and let air dry for 24 hours.

 

[day_trippr]

^agree^

Ideally, use DI or RO water for the first post-acid rinse. The rest can be tap water...

Cheers!

 

[4_Sons_Brewing]

Excellent! Thanks for the advice. Will knock that out this weekend.

 

[4_Sons_Brewing]

That's a bit of rust. It's time for 3 gallons of water mixed with 1 pound of citric acid, heat and hold at 150F for 2 hours. Then rinse and let air dry for 24 hours.

Bobby - quick follow up, I assume the 3 gallons / 1 pound is scalable, I may need more than three gallons to keep my heating element submerged, so I just want to confirm that on the ratio’s.

Another question - would this solution work to remove buildup from my boil kettle (hop / wort staining)?

Any issue recirculating / pumping it from HLT to boil kettle, or would I risk damaging the pump / hoses?

 

[day_trippr]

3 gallons to 1 pound of CA is a 4% solution that you can scale to swimming pool volume if necessary

Acid cleaning can be very effective for a range of stains, though it may not get all of them (just today I was acid cleaning my boat and as usual quite happy how well that worked with minimal effort). I use Citric Acid - typically 5% and hot - to clean up accessories like tubing brushes, colanders, hop spiders/blockers and the like, as well as occasionally treating The Spousal Unit's pots when they develop any rashes.

It should not present any problems with stainless gear, pumps or hoses, either...

Cheers!

 

[4_Sons_Brewing]

Thanks Day Tripper! Appreciate the response.

 

[IslandLizard]

I guess you could recover and store that citric acid solution for a future use inside containers that are inert to acids.

 

[day_trippr]

Probably more work and risk than the $7 pound of CA powder is worth. Plus it would have some possibly interesting contaminants...

Cheers!

 

[Bobby_M]

I guess you could recover and store that citric acid solution for a future use inside containers that are inert to acids.

It actually goes rancid, or at least that's the first word that came to mind when I found a bucket of solution that was sitting for a while.

 

[MaxStout]

Citric acid is cheap. Make up a fresh solution each time.