All this talk of more wear on a pump
And battery because of 2 mill difference.
My last system (pump and battery) lasted 6 years with microbore before I sold it on.
I really don’t think it alters the life time of pumps and battery. If it does, it’s tiny.
It must mean something. In the early days Williamson pumps would only offer warranty on Shurflo pumps if they had been used with 1/2" hose.
I opted for minibore as it was closer to standard 1/2" hose than microbore was. I decided that I would 'carry' my own warranty on using a Shurflo pump with minbore, a decision I never regretted as it was so much easier to manage than 1/2" hose, especially in winter with cold water.
Microbore is just over half the internal area (volume) of minibore, so 2mm diamt makes a big difference.
(minibore = 50.27mm2.
Microbore = 28.27mm2.
1/2" hose = 530.93mm2 - 5.5 times the internal area of minibore.)
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