Why is my brand new compressor model P1.5IU-A9 not building up air pressure?
Some assembly is required before starting your P1.5IU-A9 compressor, including attachment of the wheels and handle, filling the pump with oil, and installing the air filters.
As part of this process, be sure to remove the plastic air intake plugs from the two air heads (see arrows in image below) and install the two air filter assemblies by screwing them into the open ports.
This will allow clean, fresh air to be drawn into the pump for compression.