Fire Tube Boiler Maintanance

At all times, follow the boiler manufacturer's maintenance instructions. If they aren't in the manual that was supplied with the equipment, contact the manufacturer directly for advice.

can a specialist who does this as a business - stay away 1000 ft when he is doing it.

After - get a reliable softening plant and hire a consultant to check and advice on chemical dosage every month.

A reply to your question depends on why you want to use acid clean on the water side?. Is there a build-up of scale due to inadequate water treatment? -and if so what is the scale composition?. You have already been given the correct answers for your standard of knowledge on the subject.

There are people who specialise in such cleaning for removal of scale build up. You need them to check and recommend their process with a guarantee against damaging the boiler furnace tube during the process.

On your own risk and without any guarantee of any kind, use a mild acid like citric acid diluted to 1 in 100.....you need to fill the boiler to cover the tube and leave it for some time. A little heating to 50-60 deg C will help accelerate. You might need to repeat. AT THE END, SOME METAL WILL BE DEPLETED FROM ANY EXPOSED PARTS (not covered with scale).

I actually made an experiment, by soaking 2 boiler tubes in an HCL(concentrated straight from the supplier i.e 33%) bath, 1 clean, un scaled and the other had heavy scaling. My experiment took 15hour(with constant monitering) & the results were overwelming, the unscaled was un attacked ( at least observing with the eye) and the scaled one was cleand!

along with the previous comments i should suggest that you consider, it will take a long process to clear the boiler of the smell after an acid cleaning.. i mention this if your considering this in a bakery environment. proofing doughs.