Welcome to the forum. Although you can post in any forum, the USA forum is here in case of local regs or laws
You are under no obligation to sort anything like ratios or that. It is simply a report. I charge more if it needs servicing. It's like people phoning saying my boiler needs a service, you get there and it is a repair they need.
Reply to the thread, titled "Doing cp12" which is posted in UK Plumbers Forums on Plumbers Forums.
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