Water Level Controls and Devices. A water column is used on a steam boiler to reduce the turbulence and fluctuation of the water level so the gage glass can provide a steady, accurate water level reading. The use of a water column is not mandatory.
Preparation. Verify the paint is completely dry. Never use varnish to seal acrylic paint if it is even slightly wet. Dust the surface of the dry paint gently with a clean cotton rag or paper towel. Rinse a jar or cup with water to remove any dust particles. Read the label on your varnish to find the correct water-to-varnish ratio. Mix the varnish with water in the jar or cup.
If the painted concrete floor is in an area that experiences heavy foot traffic or contains a lot of furniture, a concrete sealant is necessary to protect the paint from peeling, flaking, wearing off or getting scratched.. Attach a long arm to a roller brush and begin working the sealant onto the painted concrete floor. Be sure to start at one side of the room, and work toward the door to avoid painting yourself into a corner.