The victim, who lived in Mellor Crescent, let the man in after there were problems with the water supply in the road at the weekend.
While the pensioner was distracted, another thief sneaked into the house and stole £70 before both men escaped.
On Monday, elderly residents in Mellor Crescent again called police after a man - in his sixties and wearing blue jeans and glasses - started knocking on their doors asking to buy jewellery.
He was wearing a multi-coloured cycle helmet and was riding a mountain bike.
Yesterday (Tuesday), police Sergeant Kevin Fryer warned that thieves were targeting homes.
"These crimes are about at this time of year because people keep valuables, presents and money in their houses for Christmas," he said.
"If anyone has any doubt they should ask for identity cards and if they are still not happy they should contact us."
Knutsford police can be contacted on 01625 536222.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article