I have to measure level in condensing pot . the hole size in pot is 10 mm, but level stub is 25mm ID pipe with DN25 valve. wat rectification can be done . whether there is any standard for level hole just as 10mm for pressure hole.
There is no 'standard' for a port size on a condensing pot. The port size is what it is.
If the centerline offset between the existing 25mm port and your desired 10mm port actually makes a difference to level measurement technology you intend using and the results that technology will provide (7.5mm), then have an adapter fabricated that places a 10mm port at the appropriate location.
See #1↑. If in doubt, talk to an experienced Instrument Technician.
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