Cleaning Hottop

[Nucer]

Okay after replacing the heater and cleaning out the chaff, I noticed how dirty the machine is.  So a friend said to put the parts in an airtight bag with ammonia.  I was very skeptical but I thought I would give it a try.  Well I left the parts in the bag for 3 days (yeah I was going for one day but I forgot about it).  Well to my surprise it worked!  I rinsed off the part (rotating drum) and it sparkled like it was brand new.  No scrubbing, no work just a quick rinse.

Now two questions: first, what did this soaking do to the metal and second, can this method be used on plastic?  I suspect that chemically the metal has been affected and that no I can't use it on plastic. I am happy with the way the drum looks and have put several other pieces in a bag with ammonia.  I will keep you posted on how it works out.

(happy to see the shining drum in the hottop in Benbrook, Texas)

[JW]

Ammonia is corrosive.
That said, I'm not sure what type of steel the hottop drum is made of , but from my lab experience 304 stainless steel (the most common grade) does not corrode or react with ammonia at a household strength level (5-10%). I still wouldn't tempt fate and leave it for 3 days again.  I'm unsure on the plastics as some are non reactive with ammonia, but I wouldn't risk that either.

[BoldJava]

Ammonia is corrosive.
That said, I'm not sure what type of steel the hottop drum is made of , but from my lab experience 304 stainless steel (the most common grade) does not corrode or react with ammonia at a household strength level (5-10%). I still wouldn't tempt fate and leave it for 3 days again.  I'm unsure on the plastics as some are non reactive with ammonia, but I wouldn't risk that either.

JW, might you give a quick lesson on what goes into difference numbers/grades of stainless steel for those of us who might want to learn?

[Nucer]

Apparently this a good method for cleaning and there did not appear to be any damage to the drum.  No discoloration, no obvious thinning of material, and the only change was the removal of the crud (oils).  I did not immerse the parts in the ammonia but rather let the ammonia evaporate to a gaseous state.  So for now this seems like a way to clean the roaster parts.  I will keep y'all in the loop on how the parts are affected since I do plan on using this method again.

(still in Benbrook, Texas)

[GC7]

The Cafeza detergent we use for cleaning coffee oils backflushing our espresso machines is greaat for cleaning all parts of the hottop. Make a nice hot solution and soak away. Plastic parts wipe clean as well.

[SJM]

What about that huge bottle of Simple Green that I bought to clean the Behmor?

[expy98]

I also use backflushing detergent, it's great for the drum and other metals and the filters but
it's not so great for the front drum cover.  It'll eat away the threads for the four small screws
holding in the front glass.

[rgrosz78]

The Cafeza detergent we use for cleaning coffee oils backflushing our espresso machines is greaat for cleaning all parts of the hottop. Make a nice hot solution and soak away. Plastic parts wipe clean as well.

I literally disassemble my Hottop every 6-12 months and put all the pieces into a big plastic bucket with the Cafiza solution. Most things come out clean in 2-4 hours. Heavy residue needs to soak overnight.

[smico]

I put the drum in kitchen oven when we do self-cleaning. Comes out clean, with nice golden patina.

[ecc]

Ammonia is corrosive.
That said, I'm not sure what type of steel the hottop drum is made of , but from my lab experience 304 stainless steel (the most common grade) does not corrode or react with ammonia at a household strength level (5-10%). I still wouldn't tempt fate and leave it for 3 days again.  I'm unsure on the plastics as some are non reactive with ammonia, but I wouldn't risk that either.

JW, might you give a quick lesson on what goes into difference numbers/grades of stainless steel for those of us who might want to learn?

There are lots of ways to describe steel alloys.  Stainless mostly refers to alloys with enough chromium to form an oxide layer to protect it.  There are three main types of stainless steel, and many grades.

http://en.wikipedia.org/wiki/SAE_steel_grades

18/8 (18% chromium, 8% nickel) and 18/10 are common A2 stainless or type 304 austenitic steel.  Very corrosion resistant.
http://en.wikipedia.org/wiki/Austenitic

Martensitic steel (iron and chromium, often with a lot of carbon) is often used for expensive knives and old weapons.  It is stiffer and can be hardened (tempered)  but is much less resistant to corrosion.  I wouldn't be soaking any high end knives in that ammonia.  It is also magnetic.  Ferritic steel is also magnetic, whose chief property is temperature resistance.  It wouldn't be a good idea to soak your muffler in ammonia, either.

[BoldJava]

Thanks ECC.  Had forgotten my high school chemistry so I did a little reading on chromium.  http://www.greatmining.com/chromium.html

[Nucer]

Again it is not the liquid ammonia that does the job.  It is the gaseous state that does the trick.  Found out from my friend that he got the idea from a cooktop manual.  So go figure.  I will use whatever method is easiest and doesn't show damage to parts.

Just thought I would share this experience with the group.

(Trying to be a nice guy in Benbrook, Texas)

[rgrosz78]

I also use backflushing detergent, it's great for the drum and other metals and the filters but
it's not so great for the front drum cover.  It'll eat away the threads for the four small screws
holding in the front glass.

I haven't seen that problem yet. But I did notice some rusting of the thread for the small screw on the "Gold Knob" used to attach the front cover to the bearing plate.

[expy98]

just to clarify, it's not eating the threads on the screws, it's eating the threads on the front cover
where the 4 small screws fasten down glass.  Not sure what material the front cover is made
of but it's def not very tolerant of the detergent.  I can now only use two screws and they're barely hanging on. 

The detergent can also eat away chrome plating as well.  Careful what and how long you soak stuff in it.