From the article:
“A lot of the oil companies also have what they call “Class A” oil burners installers license. This is a good thing as you know the installer at least knows his/her profession.
Always ask anyone working on your piping for a license whether it be an Oil installers license, a LMP (Licensed Master Plumber) or a stationary engineer license. This is for your protection.”
As a homeowner, be aware that there is only one question on the plumbing test regarding heating. The LMP knows heating because of OJT, the more experience, the better. The “Class A” oil license requirement is for only one person in the company to actually possess it, make sure you get the one who does have it to show you. A stationary engineer knows almost nothing about residential heating equipment unless they worked outside the industrial settings the license is designed for, that is, in actual trained residential factory certified work.
In our litigous society, the only qualified person is one with a plumbing license and/or years of experience AND actually has the factory service procedure book and checklist in his hands while servicing the particular model number and serial number of THAT appliance. General knowledge no longer applies to appliance service; intelligent guess based upon experience is not defendable in court as the service manual says to follow factory procedure specified by the factory engineers.
So infloor heating performed by a trained contractor from factory designed plans to their specifications is the only defendable installation practice, and even then, it is subject to lady luck.