The purpose of a 3-way control valve is to shut off water flow in one pipe while opening water flow in another pipe, to mix water from two different pipes into one pipe, or to separate water from one pipe into two different pipes.
“According to “ components for fire protection
“According to” components for fire protection, are products or fire pump sets which are built according to specifications written in fire protection standards – for example “according to NFPA 20”. These products are not listed and haven’t been evaluated by a listing laboratory.
To prevent corrosion and problems with operation, heating and air-conditioning systems must be constructed so that air can be removed both when the system is filled and during subsequent operation.