This issue came up earlier today.....
Ohio Code:
"§ 5321.07 Notice to landlord to remedy condition; deposit of rent with court or other remedies.
(A) If a landlord fails to fulfill any obligation imposed upon him by section 5321.04 of the Revised Code, other than the obligation specified in division (A)(9) of that section, or any obligation imposed upon him by the rental agreement, if the conditions of the residential premises are such that the tenant reasonably believes that a landlord has failed to fulfill any such obligations, or if a governmental agency has found that the premises are not in compliance with building, housing, health, or safety codes that apply to any condition of the premises that could materially affect the health and safety of an occupant, the tenant may give notice in writing to the landlord, specifying the acts, omissions, or code violations that constitute noncompliance. The notice shall be sent to the person or place where rent is normally paid.
(B) If a landlord receives the notice described in division (A) of this section and after receipt of the notice fails to remedy the condition within a reasonable time considering the severity of the condition and the time necessary to remedy it, or within thirty days, whichever is sooner, and if the tenant is current in rent payments due under the rental agreement, the tenant may do one of the following:
(1) Deposit all rent that is due and thereafter becomes due the landlord with the clerk of the municipal or county court having jurisdiction in the territory in which the residential premises are located;
(2) Apply to the court for an order directing the landlord to remedy the condition. As part of the application, the tenant may deposit rent pursuant to division (B)(1) of this section, may apply for an order reducing the periodic rent due the landlord until the landlord remedies the condition, and may apply for an order to use the rent deposited to remedy the condition. In any order issued pursuant to this division, the court may require the tenant to deposit rent with the clerk of court as provided in division (B)(1) of this section.
(3) Terminate the rental agreement.
(C) This section does not apply to any landlord who is a party to rental agreements that cover three or fewer dwelling units and who provides notice of that fact in a written rental agreement or, in the case of an oral tenancy, delivers written notice of that fact to the tenant at the time of initial occupancy by the tenant.
(D) This section does not apply to a dwelling unit occupied by a student tenant."
And
"§ 5321.04 Obligations of landlord.
(A) A landlord who is a party to a rental agreement shall do all of the following:
(1) Comply with the requirements of all applicable building, housing, health, and safety codes that materially affect health and safety;
(2) Make all repairs and do whatever is reasonably necessary to put and keep the premises in a fit and habitable condition;
(3) Keep all common areas of the premises in a safe and sanitary condition;
(4) Maintain in good and safe working order and condition all electrical, plumbing, sanitary, heating, ventilating, and air conditioning fixtures and appliances, and elevators, supplied or required to be supplied by him;
(5) When he is a party to any rental agreements that cover four or more dwelling units in the same structure, provide and maintain appropriate receptacles for the removal of ashes, garbage, rubbish, and other waste incidental to the occupancy of a dwelling unit, and arrange for their removal;
(6) Supply running water, reasonable amounts of hot water and reasonable heat at all times, except where the building that includes the dwelling unit is not required by law to be equipped for that purpose, or the dwelling unit is so constructed that heat or hot water is generated by an installation within the exclusive control of the tenant and supplied by a direct public utility connection;
(7) Not abuse the right of access conferred by division (B) of section 5321.05 of the Revised Code;
(8) Except in the case of emergency or if it is impracticable to do so, give the tenant reasonable notice of his intent to enter and enter only at reasonable times. Twenty-four hours is presumed to be a reasonable notice in the absence of evidence to the contrary.
(9) Promptly commence an action under Chapter 1923. of the Revised Code, after complying with division (C) of section 5321.17 of the Revised Code, to remove a tenant from particular residential premises, if the tenant fails to vacate the premises within three days after the giving of the notice required by that division and if the landlord has actual knowledge of or has reasonable cause to believe that the tenant, any person in the tenant's household, or any person on the premises with the consent of the tenant previously has or presently is engaged in a violation as described in division (A)(6)(a)(i) of section 1923.02 of the Revised Code, whether or not the tenant or other person has been charged with, has pleaded guilty to or been convicted of, or has been determined to be a delinquent child for an act that, if committed by an adult, would be a violation as described in that division. Such actual knowledge or reasonable cause to believe shall be determined in accordance with that division.
(B) If the landlord makes an entry in violation of division (A)(8) of this section, makes a lawful entry in an unreasonable manner, or makes repeated demands for entry otherwise lawful that have the effect of harassing the tenant, the tenant may recover actual damages resulting from the entry or demands, obtain injunctive relief to prevent the recurrence of the conduct, and obtain a judgment for reasonable attorney's fees, or may terminate the rental agreement."
Source:
http://onlinedocs.andersonpublishing.com/revisedcode/index3.cfm?GRDescription1=revised code&GRDescription2=title 53&GRDescription3=&TextField=<JD:"5321">CHAPTER 5321: LANDLORDS AND TENANTS&GRStructure1=5321&GRStructure2=