Neither the Commission nor any of its members shall direct or request the appointment of any person to, or his removal from office by the City Manager or by any of his subordinates or in any manner take part in the appointment or removal of officers and employees in the administrative service of the city. Except for the purpose of inquiry, the Commission and its members shall deal with the administrative service solely through the City Manager and neither the Commission nor any member thereof shall give orders or make request of any subordinates of the City Manager, either publicly or privately.