Boiling water through pump

[Razorback_Jack]

I just purchased a magnetic drive pump that says it’s rated up to 240 degrees. If I’m transferring boiling (or nearly boiling) water/wort through it, I’m still worried about subjecting the hoses to fluid that hot. The hose I bought is 1/2” high-temp silicone hose, made by Midwest Home Brewing. However, doesn’t say what temp it’s rated for. Should this be a concern?

jackson

 

[RPh_Guy]

Silicone is perfectly fine at boiling point and can go much higher.

 

[SanPancho]

Silicone is perfectly fine at boiling point and can go much higher.

This is woefully incomplete information and reckless.

DO NOT put boiling liquids in silicone hoses under anything higher than gravity-fed pressure. Buy braided silicone for any installation using mechanical (i.e. pump) pressure and boiling liquids.

Even homebrew pumps are capable of bursting regular silicone hoses in cases of user error, blockage, hose damage (typically unnoticed), etc.

 

[RPh_Guy]

Homebrew magnetic drive (centrifugal) pumps don't generate enough pressure to burst silicone.

https://www.morebeer.com/products/high-temp-silicone-tubing-12-id.html
Working pressure max 20psi (burst pressure of 30psi)

https://www.midwestsupplies.com/products/1-2-id-silicone-tubing
Midwest lists the same burst pressure, 30psi.

A Riptide pump generates a maximum of 9psi, for example. (21ft max head)

Normal silicone tubing is widely used by homebrewers with pumps. Homebrewing hardware industry leaders all use and recommend normal silicone tubing with pumps.
https://www.brewhardware.com/product_p/siliconetubing12id.htm

Silicone is rated to over 500°F, so any kind of melting isn't a problem, and it's inert so there's no flavor transfer.

 

[day_trippr]

It's always prudent to assess risk, not all rigs will perform the same due to lift differences and pump capabilities, and anyone not comfortable going "nekkid" should opt for the pricey reinforced silicone.

That said, fwiw, I've been running a pair of March 815pls with typical 1/2" ID - 3/4" OD non-reinforced silicone tubing (latest batch is the "nearly-clear" stuff @Bobby_M has been selling) on my herms rig with zero issues. Never even a hint of a bubble even when slamming the pump against a full-stopped output ball valve.

The same tubing will instantly fail using household water pressure against a stopped valve, so it's evident the pump can't deliver high enough static pressure...

Cheers!

 

[RPh_Guy]

There's no guesswork involved regarding pressure. Pumps list the max head in the specs.

 

[Bobby_M]

Your post is also incomplete. The max pressure of tubing is based on wall thickness, material, temp, etc. Most thickwall silicone, that is 1/2" ID with 1/8" walls, can handle pressure from mag drive homebrew pumps all day.

Silicone also barely softens with heat.

This is woefully incomplete information and reckless.

DO NOT put boiling liquids in silicone hoses under anything higher than gravity-fed pressure. Buy braided silicone for any installation using mechanical (i.e. pump) pressure and boiling liquids.

Even homebrew pumps are capable of bursting regular silicone hoses in cases of user error, blockage, hose damage (typically unnoticed), etc.

 

[Stand]

Silicone reinforced tubing so far as I can tell is also capable of sustaining damage.

Clogs don't change the maximum pressure of the pump.

I have been know to run with scissors, but this ain't that.

 

[Deadalus]

While I am not so worried about the boiling temps, I will mention that for some brew rig configurations the braided silicon hoses may be helpful to prevent bends. I've got three hoses that work with both my MT and BK. The hoses, which are perhaps a tad on the thin side, don't always line up optimally with the pump. Less of a problem since I reconfigured and threw an elbow in. I also took a short length of 12 gauge insulated copper line and looped it around the outflow tubing from the pump. A few loops around the tubing starting near the quick disconnect helps make a more gradual bend. I made sure to cut the copper clean and not let it dig into the tubing.

When I replace the tubing I will make sure to get a thicker wall or maybe go the reinforced route.

 

[SanPancho]

Well then you must obviously be the expert.Especially (?) since youve never actually seen it happen. Im just exaggerating the thing i saw with my own eyes. Totally.

 

[SanPancho]

Silicone reinforced tubing so far as I can tell is also capable of sustaining damage.

Clogs don't change the maximum pressure of the pump.

I have been know to run with scissors, but this ain't that.

yeah. I described the difference between damaged silicone snd damaged silbrade. Read the whole thing next time maybe. The results are not the same in severity. Not at all.

 

[augiedoggy]

I just purchased a magnetic drive pump that says it’s rated up to 240 degrees. If I’m transferring boiling (or nearly boiling) water/wort through it, I’m still worried about subjecting the hoses to fluid that hot. The hose I bought is 1/2” high-temp silicone hose, made by Midwest Home Brewing. However, doesn’t say what temp it’s rated for. Should this be a concern?

jackson

First things first..
The pump is rated for 240 degrees with liquids such as oil that can go to 240 degrees in liquid state. NOT with water or wort which boils and starts to convert to steam at 212.. This will cause cavitation which can damage the pump over time. Its a common for pump companies to advertise this because of the different types of liquids that can reach temps higher than 212 while maintaining a stable liquid form.

It will work but you cavitation (that noise you hear when theres gas vapor mixed with water in the pump head) can cause the magnetic head to take a beating or (unlikely if rated to 240) things to sometimes warp and there are many threads debating this.

Nearly boiling or post boil liquid is fine for these pumps. I'm just throwing this out there for folks trying to pump while actually continuously boiling.. its just not a good idea.

 

[RPh_Guy]

Well then you must obviously be the expert.Especially (?) since youve never actually seen it happen. Im just exaggerating the thing i saw with my own eyes. Totally.

Always with the insults and sarcasm. Can you not have a discussion without acting like a child?

The probability of the event occurring matters when deciding if it's worthwhile taking extra steps or spending extra money to prevent it.

I'm curious; what kind of pump caused tubing to burst?

NOT with water or wort which boils and starts to convert to steam at 212.

It takes a lot of energy to vaporize water. It doesn't happen to a significant degree once it's pumped outside the kettle. If there is a cavitation issue for some reason, the fix is simple. Turn the pump off for a few seconds, which allows bubbles to escape, and reduce the flow when you turn it back on.

Just like using normal silicone tubing, it's common practice to circulate boiling wort through a heat exchanger to sanitize it.
This doesn't mean it's absolutely the best practice, but it does work well.

 

[Razorback_Jack]

First things first..
The pump is rated for 240 degrees with liquids such as oil that can go to 240 degrees in liquid state. NOT with water or wort which boils and starts to convert to steam at 212.. This will cause cavitation which can damage the pump over time. Its a common for pump companies to advertise this because of the different types of liquids that can reach temps higher than 212 while maintaining a stable liquid form.

It will work but you cavitation (that noise you hear when theres gas vapor mixed with water in the pump head) can cause the magnetic head to take a beating or (unlikely if rated to 240) things to sometimes warp and there are many threads debating this.

Nearly boiling or post boil liquid is fine for these pumps. I'm just throwing this out there for folks trying to pump while actually continuously boiling.. its just not a good idea.

Thanks for this. It will be nearly-boiling, or post-boil. Probably not over 200 degrees or maybe even 190.

 

[Razorback_Jack]

This is 1/8”-thick wall, 1/2” ID white silicone rubber by Midwest Brewing, purchased on Amazon. Not sure how high-temp it’s rated, as I can’t find that info. I also don’t know what “braided” means. This is milky-white, semi-malleable tubing.

 

[RPh_Guy]

Not sure how high-temp it’s rated, as I can’t find that info.

Silicone is stable at boiling temperature, regardless of where you got it. It's an intrinsic property of silicone.

Here's an example of reinforced ("braided") silicone tubing:
https://www.morebeer.com/products/silicone-tubing-reinforced-12.html

 

[Razorback_Jack]

Silicone is stable at boiling temperature, regardless of where you got it. It's an intrinsic property of silicone.

Here's an example of reinforced ("braided") silicone tubing:
https://www.morebeer.com/products/silicone-tubing-reinforced-12.html

Thanks! It’s definitely not braided, what I purchased.

 

[Razorback_Jack]

Thanks! It’s definitely not braided, what I purchased.

Also, I won’t be using with any stoppage. In other words, the liquid will flow freely from below the mash basket to the top of the mash. Then when cooling, again circulating from the valve to the top of the liquid. For cleaning, I’ll be circulating from a hot kettle to my keg... just through the open lid, not through posts. So I probably shouldn’t worry about bursting, I wouldn’t think.

 

[DaveBrew17]

I have found this post to be very helpful as I had the same question. Glad looked before I posted. Thanks guys!

 

[augiedoggy]

It takes a lot of energy to vaporize water. It doesn't happen to a significant degree once it's pumped outside the kettle. If there is a cavitation issue for some reason, the fix is simple. Turn the pump off for a few seconds, which allows bubbles to escape, and reduce the flow when you turn it back on.

Just like using normal silicone tubing, it's common practice to circulate boiling wort through a heat exchanger to sanitize it.
This doesn't mean it's absolutely the best practice, but it does work well.

I dont wish to argue about it
but from my from experience from both a seized pump as well as the very loud racket my big whirlpool pump makes when I accidentally turn it on while theres still a boil that cavitation is not really that difficult to get when pumping boiling temp liquid. there are threads where reps from some of the pump companies recommend against it for all but a very short period of time

 

[RPh_Guy]

I dont wish to argue about it
but from my from experience from both a seized pump as well as the very loud racket my big whirlpool pump makes when I accidentally turn it on while theres still a boil that cavitation is not really that difficult to get when pumping boiling temp liquid. there are threads where reps from some of the pump companies recommend against it for all but a very short period of time

Why do you think it happens some times but not others? The positioning of the pump output?

 

[augiedoggy]

Why do you think it happens some times but not others? The positioning of the pump output?

I would venture to guess in some cases the long length of hose some use might create enough cooling in the line to diminish it. Those that have the old school traditional setups with pumps mounted down below the table and are using 5-6 ft of uninsulated silicone hose may be experiencing enough passive cooling where its not an issue.. IDK really. I do know that every time I start my whirlpool on my 3bbl setup I have to start with the pump opened about half way and once the wort gets down to say 204 I can open the output valve more without the rattle. and this is with a 3/4hp sanitary pump on wheels which only knows one position.

 

[day_trippr]

I believe the answer to pump cavitation with boiling - or "almost boiling" - liquids involves this:

Cheers!

 

[SanPancho]

I would venture to guess in some cases the long length of hose some use might create enough cooling in the line to diminish it. Those that have the old school traditional setups with pumps mounted down below the table and are using 5-6 ft of uninsulated silicone hose may be experiencing enough passive cooling where its not an issue.. IDK really. I do know that every time I start my whirlpool on my 3bbl setup I have to start with the pump opened about half way and once the wort gets down to say 204 I can open the output valve more without the rattle. and this is with a 3/4hp sanitary pump on wheels which only knows one position.

the nano had a similar issue on the 100gal. we think that either the elements were still so hot that we'd get localized boiling at the kettle bottom, or that the convection coming off the elements was enough to cause a bit of negative suction type pressure in the downtube. (which sat right under the elements) maybe both. who knows? half way throttled and there wasnt an issue for the pump. but the first times we opened it wide at FO there were some noises that didnt sound so good. that was only a 1/3 horse.

 

[RPh_Guy]

If you beat your equipment all to crap, running it over with chairs and whatnot, I could see the value of using reinforced tubing. I'll be waiting for the video.

On the other hand, if you treat your equipment with care, normal tubing will last indefinitely.

Cheers

 

[Bobby_M]

So much drama. There are a few dozen ways to injure or kill yourself brewing and it would help for all of us to think of worst case scenarios from time to time. You know of someone that got hurt using some version of silicone tubing in some situation. There are threads about bad cuts from glass carboys. There must be over a 10 Million glass carboys out there in regular use and the internet made it possible for us to concentrate injury stories from a couple dozen people.

Just being in proximity to 10 gallons of boiling sugar water is more dangerous than you should be willing to put up with. If the cost is no object, hey this is only $600.

 

[Bobby_M]

I believe the answer to pump cavitation with boiling - or "almost boiling" - liquids involves this:

Cheers!

Right, whenever a process requires boiling at lower temperatures, you'd intentionally pull a vacuum on it. Since most of the liquid in a kettle is at or near the atmospheric boiling point, the tubing leading into the head of a pump is under vacuum and will cause increased boiling. This can be mitigated to a point by throttling the ouput of the pump with a valve so that the vacuum is minimized. In general I've observed that homebrew pumps can run wide open when the temp is about 20F below boiling point with nearly zero cavitation. As you get closer to boiling, you have to increase the backpressure to maintain prime. Some setups have enough unintentional back pressure in the lines/fittings that you end up with the same end effect. Even if your pump doesn't completely stop which edging cavitation, it's probably not the most healthy way to run long term. There's very little reason to do this when a flame out recirc is still plenty hot for any heat sanitizing you were planning.

 

[doug293cz]

Throwing around personal insults is not allowed on HBT. If you can't have a disagreement with someone without getting personal, don't engage. Thread closed for a cooling off period.

doug293cz
HBT Moderator

 

[doug293cz]

Thread reopened. Stay on topic, and keep it civil, please.

doug293cz
HBT Moderator