Sacha Dixey, 38, charged vulnerable victims up to £17,000 to install heating systems but deliberately did not do the work, the county council said.
Dixey, of Mayfield Close, Bognor, used false names to return to his original victims and carry out further fraud, including a blind man.
Trading Standards began investigating after receiving almost 100 complaints about two companies Dixey was sole director of, both based in Chichester.
Dixey admitted 31 counts under Fraud Act, Companies Act and the Consumer Protection from Unfair Trading Regulations, according to West Sussex County Council.
As well as six years in jail, Dixey was banned from being a company director for ten years at Hove Crown Court.
David Barling, county council cabinet member for residents’ services, said: “He mercilessly preyed on the weak and the vulnerable for his own good, with absolutely no account for their feelings.”
Dixey used various false names to return to his original victims and carry out further fraud, including targeting one blind man.
Judge Niblett said his fraud against the blind man was “particularly cruel”, especially because Dixey had gone back to him a second time while on bail, the council said.
Richard Sargeant, West Sussex Trading Standards Team Manager, said: “We used Altia-ABM software to gather a robust portfolio of evidence against this man.
“The speed and accuracy of this specialist software allowed us to pinpoint the crucial pieces of evidence which underpinned the prosecution.
“Anyone who thinks they have been a victim of an unfair trading practice should contact Trading Standards.”
Ian Watson, chief executive of Altia-ABM said: “Investigative teams from Trading Standards, HMRC and police forces nationally and internationally are increasingly relying on investigation software as a key weapon in their fight against crime.
“Altia-ABM’s technology automates much of the data analysis and transaction matching, allowing trained and experienced investigative staff to home in on the key transactions that prove wrongdoing.”