The two Burnett families were actually living close together in Ramsey (in parish of Maughold)
Maughold BURNETT James 4 Albert Street Head M 63 Retired Lighthouse Keeper --- born Scotland
Maughold BURNETT Catherine 4 Albert Street Wife M 59 --- Michael IoM
Maughold BURNETT Catherine E. 4 Albert Street Daur U 32 Dressmaker Liverpool England
Maughold BURNETT Robert A. 4 Albert Street Son U 22 Joiner --- Scotland
Maughold BURNETT Margaret E. 4 Albert Street Daur U 28 Servant Domestic --- Scotland
Maughold BURNETT Mary 4 Albert Street Granddaur U 3 --- --- Scotland
Maughold BURNETT John J. 2 Market Sq Head M 35 Merchant --- IoM
Maughold BURNETT Margaret 2 Market Sq Wife M 25 --- --- Scotland
Maughold BURNETT Catherine E. 2 Market Sq Daur U 6 --- --- Scotland
Maughold BURNETT Jessie B. 2 Market Sq Daur U 4 --- --- Indian Ocean At Sea
Maughold BURNETT James 2 Market Sq Son U 1 --- --- Scotland
Maughold BURNETT Isabella 2 Market Sq Servant U 14 Servant --- Scotland

in 1883 BURNETT J. J., MINERAL WATER MANUFACTURER, PROMENADE
Burnett Mrs. J., apartments, 43 Waterloo road

In 1889 directory Michael - Burnett Kate, grocer, The Village

around 1914 the Burnett's were associated with the Swan Hotel, Ramsey

several of the early Burnett deaths were in Bride - assuming these were related then possibly connected to Point of Ayre lighthouse - staff were moved (as promotion prospects became available) between lighthouses - most of which seemed to be built to a standard pattern (eg the point of Ayre light house keepers house is virtually the same as the one at the north of the Isle of Lewis) - staff records should be available from norther Commissioners of Lights but I'm not sure where their archives are now as the edinburgh offices were closed a few years ago.