What matters is the contract entered into by the erstwhile consumer with the Board. The Board cannot seek the enforcement of contractual liability against the third party. in your case previous owner had failed to pay . electricity distributor as well as mahangar gas ought to take legal proceedings against previous owner .
Haryana State Electricity Board v. Hanuman Rice Mills, Dhanauri, (2010) 9 SCC 145 = AIR 2010 SC 3835 :
"12. The position therefore may be summarised thus:
(i) Electricity arrears do not constitute a charge over the property. Therefore in general law, a transferee of a premises cannot be made liable for the dues of the previous owner/occupier.
(ii) Where the statutory rules or terms and conditions of supply which are statutory in character, authorise the supplier of electricity to demand from the purchaser of a property claiming reconnection or fresh connection of electricity, the arrears due by the previous owner/occupier in regard to supply of electricity to such premises, the supplier can recover the arrears from a purchaser." (iii) Leitner Shriram Manufacturing Ltd. v. The Chairman, T.N.Electricity Board, 2007 (4) CTC 380 :
"9. I have given careful consideration to the submissions made by the learned counsel on either side as well as the rulings of the Supreme Court as well as this Court. Admittedly, the petitioner is not a consumer at the relevant period and there is no liability on the part of the petitioner to pay any arrears left over by the erstwhile consumer. When there is no arrears payable by the petitioner, the second respondent is bound to follow the provisions under Section 43 of the Electricity Act,2003 and provide electricity supply to the petitioner industry. When the petitioner has come forward to comply with all the requirements as contemplated under the provisions of the Electricity Act, the impugned proceedings passed by the second respondent, is not, in any way, in conformity with the provisions laid down by the said Act and therefore, the same is quashed and the second respondent is directed to provide electricity service connection to the petitioner-industry within a period of three weeks from the date of receipt of a copy of this order. However, this order shall not preclude the respondents from proceeding against the defaulter.
you are not liable to pay arrears as per abovementioned suprem court judgement . move consumer forum against mahanagar gas / electricity distributor