the installation company is perfunctory, and it is changed that this is 4 fire sprinklers, and it will take no more than 2 hours for 1 people. (It needs 4 pipe bones and 4 short pipes with a length of 18CM)

It will not affect their acceptance, and the fire sprinklers should come out.

reason 1. the installation unit is constructed according to the drawings, so it is not necessary to change who works, and it can be calculated according to the change.

2. It is possible that the installation company is conducting pressure test, and it is impossible to change the extension pipe.