Tubing diameter - does it matter

Iwf

Iwf

Iwf

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For a SSF I'm involved in I'm thinking of using smaller diameter soft tubing instead of my norm hard or standard tubing. Traditionally I've used 16/14 hard tubing or 16/10 soft. For this build I'm thinking of trying the 8mm push to fit fittings with 8mm OD and I think 5mm internal.

If I think about house heating loop, there's definitely a school of thought that uses thinner piping rather than the standard 15mm copper, but I wonder whether it makes any difference. I'll be using a DCC pump for the first time over a D5 which won't fit in the case.

Looking at JayzTwoCents he thinks things like clamping force has a greater impact on reliability. Linus found no difference in larger bore tubing, but no one seems to have tested the really small stuff.

thanks
 
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Doesn't really matter
Large diameter there's more flow
Smaller diameter there's more pressure
Either way coolant will equalise/reach saturation after been running a while

Not sure about push fit
Especially with hard tube might be
Difficult if ever need to remove
 
Mcnumpty2323 said:
Doesn't really matter
Large diameter there's more flow
Smaller diameter there's more pressure
Either way coolant will equalise/reach saturation after been running a while

Not sure about push fit
Especially with hard tube might be
Difficult if ever need to remove
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Many thanks

I've given up on hard tubing. just far too much hard work, particularly in a small case
 
I would be really careful with selecting fittings that are designed for pneumatic use in a water system. Unless the manufacturer state they are safe for water you may run in to corrosion issues in the fitting itself if the materials used are such that galvanic corrosion can occur when exposed to water, when in air you're not going to get the same type of corrosion if any. Also, some components in the fitting may just degrade anyway when exposed to water. And I am talking about different materials within the fitting itself by the way, not between the fitting and whatever it is screwed in to.

You would certainly be getting lower flow rates due to the significantly increased pressure drop in the tubes compared to standard tubing, but if this is a SFF the tube runs will be short so it may not be that significant overall, but I would want to be damn sure the fittings have been guaranteed for liquid use by the manufacturer before attempting this.
 
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Bubo said:
I would be really careful with selecting fittings that are designed for pneumatic use in a water system. Unless the manufacturer state they are safe for water you may run in to corrosion issues in the fitting itself if the materials used are such that galvanic corrosion can occur when exposed to water, when in air you're not going to get the same type of corrosion if any. Also, some components in the fitting may just degrade anyway when exposed to water. And I am talking about different materials within the fitting itself by the way, not between the fitting and whatever it is screwed in to.

You would certainly be getting lower flow rates due to the significantly increased pressure drop in the tubes compared to standard tubing, but if this is a SFF the tube runs will be short so it may not be that significant overall, but I would want to be damn sure the fittings have been guaranteed for liquid use by the manufacturer before attempting this.
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That's really good advice. I went checking and indeed, you need to be carful around the sealant products. The Amazon ones I purchased say not for drinking water use. That said a search found some that are certify for air/water use. I'll send the Amazon ones back.

Though I suspect I wouldn't end up with a problem, given I upgrade and change things almost annually, No need to take a risk when you don't need to.

Thanks again
 
Not for drinking water doesn't mean
Not for water full stop
Just means no potable water as stuff may
Leach into the water that you don't want
To be ingesting
But similar idea use stuff that's for hydraulics
Instead of pneumatics
 
It’ll gimp your flow rates and mean your temps will be a few degrees worse but if we’re talking about a SFF system I doubt you would be caring?
 
Thanks all again. I think I’ll run some tests, see what difference it makes. In fact there’s only loop element that includes a tightish bend. In putting together the standard soft tube version, it is remarkable how heavy the standard g1/4 fittings, and how small the push to fit one’s are

I’ll report back
 
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One of the forum members makes some great small form factor water cooled builds
He might be just the person to offer some advice

Have a look at minibotpc.com for some
Of his stuff
Not only are those great
But he takes seriously good photos too
Always sickens me he's too talented for one guy :cry:
@Jay85 any advice for them?
 
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