The Irishman, who has slipped to number 64 in the world, suggested that the fault lies with him and not Torrance.
"I'm not thinking of changing personnel. I've got to change something in myself, attitude or something along the lines of that," he said.
"We haven't split. We are having a break because I am getting very frustrated. Until I am ready to listen to what he has to say, we are having a break."
Torrance, the father of former Ryder Cup captain Sam Torrance, was surprised, but supportive, of Harrington's decision.
"He's like a son to me and I hope we can get back together. We've been together for 15 years and I wasn't really expecting this, but I know he's been unhappy," he said.
"His game is in a bad shape because of his mind – I've said that to him – but he's determined to make changes."
The 39-year-old, who missed the cut at the recent Irish Open, hasn't won a US or European Tour event in three years.