Harwil Corporation · Tomar Water Systems · Authorized

Find the switch by its number.

Every model, every drag-disk and shaft option, every RO membrane — with the datasheet attached and the flow range on the label. Type the model and go.

Most searched Q-8N Q-12CR Q-15 Q-4E TW-4000
Harwil flow switches available from Pure Flow Systems

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Every inline switch plotted against the flow it senses. Find your GPM on the scale, then read across.

GPM · logarithmic reference
Q-1 0.12 – 8 GPM ½″ NPT Q-4E 4 – 70 GPM 1″ NPT Q-12N / Q-12CR 0.7 – 590 GPM ½″ NPT Q-8DS 5 – 80 GPM 1″ NPT Q-10N / Q-10VCR 0.7 – 1025 GPM 1″–16″ Q-15 0.7 – 590 GPM ¾″ NPT Q-8N / Q-8CR 8 – 1900 GPM 1″–10″

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