[curiouscat]

Other than hot water are there better options to dissolve away NaCl solids plugging an equipment? Over time they seem to become rock hard & circulating water seems to be very slow at removing them.

The innards of the equipment are not very accessible outside of liquid circulation but luckily the equipment is built out of Titanium so there's some leeway about how harsh a agent I can use.

Ideas?

[Babcock_Hall]

If heat is bad, then just use room temperature water.  IIRC NaCl does not change solubility much as a function of temperature.  Sorry that I don't have any other ideas for you.

[curiouscat]

If heat is bad, then just use room temperature water.  IIRC NaCl does not change solubility much as a function of temperature.  Sorry that I don't have any other ideas for you.

Heat is OK. Just wanted to explore agents that'd do the job any better / faster than water.

[aga]

Sulphuric acid will react with the NaCl, producing HCl and Na₂SO₄, the former being a gas and the latter being fairly soluble in water, so dilute sulphuric acid should do the trick.

Be aware that it could get hot.

The HCl gas should dissolve in the water as well, however you should do it Outside (or in a fume hood) to be on the safe side.

[Borek]

Sulphuric acid will react with the NaCl, producing HCl and Na₂SO₄, the former being a gas and the latter being fairly soluble in water, so dilute sulphuric acid should do the trick.

Yes, concentrated sulfuric acid will react with NaCl producing HCl. Unfortunately, diluted sulfuric acid won't do anything.

No, there is no chemistry here that will substantially change the NaCl solubility.

OTOH if whatever is deposited inside dissolves slowly, it can be because it is not just NaCl (hard to say not knowing the composition of the liquid that circulates during normal use of the equipment). Perhaps identifying composition of the solid is the first step toward finding a better way of removing it?