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Condensing/corrosion of conventional boiler
What is going on
Possible causes and checks for: condensing/corrosion of conventional boiler.
Likely causes
- Return water <140 °F
- Add/adjust mixing valve (140 return /
- Supply)
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Source: General HVAC service practice — verify per model. Written in our own words; check the manual for your exact model.
For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.