Welcome to the forum. Although you can post in any forum, the USA forum is here in case of local regs or laws
these courses can be ok but are normally just a good chance for the manufacturer to convince you their product is superior to others
try combination boilers fault finding & repair book. john reginald. best £26 i've spent
Reply to the thread, titled "Boiler courses" which is posted in Boiler Advice Forum on Plumbers Forums.
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