You can file RTI Application to obtain a Copy of the Encumbrance Certificate.
This is to inform you that you Actions cannot be taken under RTI, hence you cannot apply for EC via RTI Application. However, if you have already applied for the same, you can obtain information in regards to Status of Issuance of the EC at the concerned Sub-Registrar Office or Tahsildar Office as the case maybe.
Sub-Registrar Office or Tahsildar Office are under the Revenue Department of respective States and are a "Public Authority" as per Section 2 (h) of the Act.
To know the further procedure to file RTI, please visit https://onlinerti.com/