I own a two family house where one apt has single phase properly run to the panel but the second apt has single phase run to its panel but one phase is disconnected and the two phase lugs are jumped together. The whole apartment is on one phase. There is no 240 equipment in the house. Is there any legal or technical reason why someone would do this? I'd like to disconnect the jumper and restore the single phase to make things legal and proper. One thing, the house is built in 1905. Someone renovated the electrical system to romex probably in the 70's. There is still a bit of knob and tube that exists. Thanks.