Descaling the water reservoir of a BUNN Soft Heat Commercial Brewer

[Mr.Peaberry]

Hi All,

I bought a used, 11 year old, Bunn Soft Heat commercial brewer with the intention of reselling it. While testing it's operational status, I discovered that the lime buildup inside the internal reservoir is so bad that the water level probe and solenoid are unable to operate as intended. This situation is complicated by the fact that replacement tanks do not seem to be available at this point...so I'm stuck with needing to descale the darn thing. I don't want to damage the tank, or use metal on metal as in using steel wool or a metal scraper. Anyone have any experience with this sort of thing and can guide me down this road??

Cheers,

Peaberry

 

[Musicphan]

Can you remove the reservoir? What is the tank made of?

I have limited experience but I did tear down / rebuild a LaMarzocco Linea. I soaked the boiler/tanks/metal parts in a citric acid. You can find citric acid in the food canning section of most hardware stores. I simply filled a plastic storage tote w/ water and CA and let the parts soak for days.

 

[Mr.Peaberry]

The tank is stainless steel. It doesn't have to be removed. I've already removed the lid of the reservoir, and anything I put inside will sit until I drain it. So citric acid may be a bit too harsh don't you think??? I know there are many products offered at Whole Latte Love, but I prefer the garden variety approaches, lol! I will likely end up doing the citric acid anyway, as I'm not going to keep the machine, and using it once to remove the scale versus continued usage may be just fine for those who restore coffee equipment of all kinds...thanks for your quick reply Musicphan...

Peaberry

 

[Musicphan]

Citric acid is super mild... is basically like lemon juice.

 

[Mr.Peaberry]

So Citric Acid turns out to be not easy to find. Yes, it is sold in 5lb boxes at restaurant supply warehouses, but for those of us who don't plan of canning a whole lot of tomatoes (tomatos? lol) there really aren't a whole lot of places to find it. I finally did, after visiting a distant WalMart where it was out of stock, at a Target store. Nobody knew what it was used for or where to find it in the store...geez! I'll let you know how this turns out. Reservoir is filled with citric acid bath for 1 day now.

 

[Musicphan]

Wow... that's surprising it was so tough to find. Maybe it's seasonal... It may take days so be patient. The citric acid basically eats up the corrosion so it take a bit of time.

 

[wmark]

How about muriatic acid ? You might have to dilute a little but I find dissolving the calcium buildup tough with weaker acids

 

[Mr.Peaberry]

Muriatic acid is not a choice for food grade surface cleaning. I used a whole 8 oz bottle in the reservoir and it worked great...now doing a second treatment which will, hopefully, remove the rest of the scale. The fact that this equipment was never maintained well in terms of the scaling in the reservoir hopefully means that it was removed from service early and was not in use for the full 11 years since manufacture date.

 

[Musicphan]

Glad to hear you have some progress. When you mix your next batch of citric acid 'water' - use hot/warm water. CA will dissolve easier in hot water.

Another thing to watch for is scum/mold/nasties built up in the plastic tubing... sometimes it worth buying new vs. trying to clean.

 

[Mr.Peaberry]

After 2nd treatment with Citric acid...still a little scale left with a distinct water line...like this machine was never well maintained or so it seems. Probably meant it was placed out of service sooner because the water level probe stopped working after a point. This 3rd treatment has already removed all the scale that was there after the 2nd batch, and it is only one day....by tomorrow the little scale left in the corners of the reservoir should be gone. This is great!! No elbow grease needed, just removing a bunch of calcium sludge from bottom of tank after first run.

 

[Musicphan]

LOL... just patience ... glad its working.

 

[Mr.Peaberry]

Patience is something I have learned well...having fathered three girls. And the tank is now good as new...very clean and free of all calcium/magnesium deposits. Can't wait to test and verify that the unit is functioning properly. Thanks for the heads-up about citric acid.

Peaberry

 

[JoeConiglioArmenia]

I operate one of these that has a slight drip from the spout & scaling around the bottom portion of the spout. Do you think this could be more than the drip causing the scaling just like your case?

 

[Mr.Peaberry]

Hi JoeCA! My guess is that the drip is caused by calcium deposits on one of the valves that prevent it from closing properly. If you haven't descaled your machine...you may want to consider doing so...but that means you would have that machine out of order for several days if you want to do a proper job. Descaling the tank was critical to the operation of the brewer I have because the mineral deposits interrupted the operation of the water level sensor and solenoid controlling the open/close switch of the fill valve.

Peaberry