Will hydrochloric acid damage the joker valve?

I used appliance descaler to unblock sink drains at home. Very effective and no noticeable fumes
Cheap too. About £10 for 5 litres from Ebay.
 
HunterWanderer said:
I used appliance descaler to unblock sink drains at home. Very effective and no noticeable fumes
Cheap too. About £10 for 5 litres from Ebay.
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Pretty high probability of it being dilute citric acid. You can buy about 1kg of 100% citric acid for around £8-£9. It's been mentioned already.

Actually does a very good job on central heating pipes. Mine were about 30 years old and heating stopped working during early part of Covid. Some people were charging £80 for Fernox DS40. I just bought citric acid and malic acid from eBay and made up my own 80:20 mix. Heating was fine after one treatment and I had enough for another 3 doses if ever needed and pretty cheap.

It would be rubbish clearing drains at home. We never ever descale anything. I think we got rid of our first electric kettle after about 30 years and the inside was still perfect with original element. Probably the softest water you'll find. I can wash the car and just let it dry without worrying about streaks if I'm in a hurry. I'd use caustic soda for a clogged drain as it wouldn't be blocked by calcium deposits in our neck of the woods.:D
 
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Concentrated hydrochloric acid is sometimes referred to as fuming hydrochloric acid and is about 37% HCl. It's unpleasant stuff to work with and unlikely to be sold for use outside of lab applications.
Lower concentrations are still very reactive. Chemistry remains the same oy the reaction is slower as concentration decreases. If it damages a metal or rubber at high concentration it will do the same at lower concentration but at a slower rate.
Citric and other organic acids are called weak acids not because they are unreactive but because only a proportion of the material forms acid whilst the rest doesn't dissociate to form a reactive chemical.
If you're clearing drains and not calcium deposits then use caustic soda.
 
Irish Rover said:
I had a blockage in one of the heads today and as I'm sure most of you know clearing it wasn't a pleasant or easy job. There was a lot of calcium build up in the discharge pipe and getting it out and back in was a bitch. Rather than face the same job in the other head I'm planning some preventative maintenance. I use hydrochloric acid in my swimming pool so I have a ready supply of it. I was planning to flush a 25% solution into the pipes and leave it to do it's business for a few hours. Changing the joker valve is a bit of a bitch on my boat as well due to restricted space so I'd hate to damage it with the acid. What do the experts say?
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The experts will tell you that the joker should be replaced every 1-2 seasons. It's probably in the manual.
 
Baddox said:
... Citric and other organic acids are called weak acids not because they are unreactive but because only a proportion of the material forms acid whilst the rest doesn't dissociate to form a reactive chemical....
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Actually, the "weak acid " refers to the solution pH (technically, the pKa). An acid can also be either dilute or concentrated.
 
Having read many horror stories about banging waste pipes on walls, I decided to give my system a treatment of brick acid. Poured a couple of litres into the system went for a lively sail and then emptied the holding tank. Felt like a red arrow with the white trail of calcium that washed out a stern. This was a couple of years ago so probably time for another dose.
 
Did you use it straight with no dilution? Does it say on the bottle what its concentration is?
 
Baddox said:
If it damages a metal or rubber at high concentration it will do the same at lower concentration but at a slower rate.
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I don't think that is true. I have a number of compatibility charts and tables for rubbers and plastics in a wide range of chemicals. The majority show separate results for dilute and concentrated acids.

In hydrochloric acid, which I use extensively for descaling, exposure is rarely needed longer than about 20 minutes before the acid is consumed and gassing stops.
 
thinwater said:
Actually, the "weak acid " refers to the solution pH (technically, the pKa). An acid can also be either dilute or concentrated.
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That's true but it's a Catch 22. To be useful the reader would need to understand the physical chemistry, in which case they don't need to be told it.
It's sufficient to understand that weak/strong is different to dilute or concentrated.
 
vyv_cox said:
I don't think that is true. I have a number of compatibility charts and tables for rubbers and plastics in a wide range of chemicals. The majority show separate results for dilute and concentrated acids.

In hydrochloric acid, which I use extensively for descaling, exposure is rarely needed longer than about 20 minutes before the acid is consumed and gassing stops.
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The difficulty with compatability charts is they need to oversimplify things to be concise.
Reaction kinetics vary with reactants' concentrations and other factors such as tempererature, catalysts, etc.
Reaction rates could be plotted as a graph versus concentrations where higher concentrations almost invariably correspond with faster reactions or apparently greater reactivity.
For someone to decide a chemical and material are (in)compatible they must first decide what reaction rate is acceptable. For example is 304 stainless steel compatible with sea water?
 
Baddox said:
The difficulty with compatability charts is they need to oversimplify things to be concise.
Reaction kinetics vary with reactants' concentrations and other factors such as tempererature, catalysts, etc.
Reaction rates could be plotted as a graph versus concentrations where higher concentrations almost invariably correspond with faster reactions or apparently greater reactivity.
For someone to decide a chemical and material are (in)compatible they must first decide what reaction rate is acceptable. For example is 304 stainless steel compatible with sea water?
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I suspect that compatibility charts reflect real life experience rather than laboratory or theoretical trials. This is what my boating experience with HCl suggests but also many years of giving advice on elastomeric seal materials selection.
 
Mistroma said:
Pretty high probability of it being dilute citric acid. You can buy about 1kg of 100% citric acid for around £8-£9. It's been mentioned already.

Actually does a very good job on central heating pipes. Mine were about 30 years old and heating stopped working during early part of Covid. Some people were charging £80 for Fernox DS40. I just bought citric acid and malic acid from eBay and made up my own 80:20 mix. Heating was fine after one treatment and I had enough for another 3 doses if ever needed and pretty cheap.

It would be rubbish clearing drains at home. We never ever descale anything. I think we got rid of our first electric kettle after about 30 years and the inside was still perfect with original element. Probably the softest water you'll find. I can wash the car and just let it dry without worrying about streaks if I'm in a hurry. I'd use caustic soda for a clogged drain as it wouldn't be blocked by calcium deposits in our neck of the woods.:D
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Our sink drains were blocked with limescale and the descaler ( probably citric acid ) cleared it completely with no smell or fumes.
It's made for descaling dishwashers etc so should be good on rubber seals etc like joker valves at the concentration as supplied.
 
HunterWanderer said:
Our sink drains were blocked with limescale and the descaler ( probably citric acid ) cleared it completely with no smell or fumes.
It's made for descaling dishwashers etc so should be good on rubber seals etc like joker valves at the concentration as supplied.
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Unlikely to harm the valves, even with a saturate solution. Ditto HC l at moderate concentration. Of course the HCl will be more dissociated. I only use moderate amounts of HCl as I'm careful to avoid calcification in the first place. It's more of a final treatment to remove any vestiges. Citric would do as well for that but Agua fuerte is readily found in all med. countries.
 
CJU said:
Did you use it straight with no dilution? Does it say on the bottle what its concentration is?
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No. I think that it is has to be diluted anyway to sell it these days. It does sting a little bit if you splash it on your skin but it does not destroy you or leave any marks.
 
jaminb said:
No. I think that it is has to be diluted anyway to sell it these days. It does sting a little bit if you splash it on your skin but it does not destroy you or leave any marks.
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My pool acid is, I'm told, 36% concentrate, and I can assure you it does leave a mark on bare legs if splashes are not washed off almost immediately.
 
Irish Rover said:
My pool acid is, I'm told, 36% concentrate, and I can assure you it does leave a mark on bare legs if splashes are not washed off almost immediately.
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I tolly agree the pool acid i use is of a similar concentration and I use it for removal of head crud as well as rust on my steel boat
 
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