The new three-year contract is worth more than £700,000 and builds on the existing partnership between the two organisations.
Liberty has been doing gas boiler installations for the landlord for the past three years – with customer satisfaction rates from that service at almost 99%.
The firm already delivers gas servicing and repairs to East Devon District Council and Mid Devon District Council.
A team of seven staff including a gas engineer apprentice will be employed on the contract, creating local jobs.
Chris Gilmore, Liberty Operations Director, said: “Our work to deliver gas servicing and repairs work for North Devon Homes is now underway. We are delighted to be expanding on the existing work we do for them.”