Descaling Large Equipment

Tim Fregeau from Goodway joins us to talk about descaling large equipment. He also discusses best practices and why they matter to you.

Scale refers to mineral deposits that build up in any water source. Water can be brackish, rusty, muddy, or otherwise high in mineral content, and those minerals begin to accumulate on heat-transfer surfaces on large equipment. Scale can cause metallic components to weaken and leak, and it can block microchannel coils. The large equipment can't reject the heat efficiently or function as it should when it has scale buildup, so that's where descaling comes in.

When it comes to chillers, you can either brush or chemically clean the tubes to remove scale. There will be times when you physically cannot brush the tubes, so you must rely on chemicals to descale the equipment. When you use chemicals, you pump the chemical solution into a low point of the condenser and make it come out of a high point. Factors that influence success are the chemical makeup, flow rate, and pump size. Boilers are quite similar to chillers, but the higher water temperatures come into play.

Various chemical agents have different functions. Acids dissolve calcium, and inhibitors protect the base metals. Wetting agents reduce the surface tension and allow the chemicals to spread out. Penetrating agents allow the chemicals to get deeper into the mineral deposit to dissolve calcium and free up the rest of the deposit.

Tim and Bryan also discuss:

  • Plate heat exchangers
  • Separating open loops from chillers
  • Goodway clean-in-place systems
  • Chemical selection and dilution
  • Circulation time
  • Why track oil levels and approach temperatures?
  • Compression ratio and system efficiency
  • Common cleaning challenges and mistakes to avoid
  • Water pH
  • Calcium spot tests
  • Goodway products
  • Legionella

Check out Goodway's site HERE.

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