Is a party entitled to rely on an express warranty?

A party is not required to demonstrate reliance on express warranties to succeed in a claim based on them. They are entitled to rely on them (Monarch Construction Limited v. Axidata Inc. 2007 CanLi 6579 (ONSC pages 41 and 42)).

In Davis v. Kelly 2001 P.E.S.C.T.D. 98, DesRoches C.J.T.D. stated at paragraph 35: A warranty is the assurance by one party to a contract of the existence of a fact upon which the other party to the contract may rely. It is an assurance given by the promissor to the promissee in order to relieve the promissee of any duty to ascertain the fact for himself or herself. It is a term of the contract, but is collateral to the main purpose of the contract; that is to say it is not so vital as to negate the agreement if the warranty is not true. However, if the warranty is untrue, it can give rise to an action for damages.