Any process that decreases the rate, frequency or extent of canonical Wnt receptor signaling pathway that positively regulates heart induction. Canonical Wnt receptor signaling pathway involved in heart induction is the series of molecular signals initiated by binding of a Wnt protein to a frizzled family receptor on the surface of the target cell, followed by propagation of the signal via beta-catenin, and ending with a change in transcription of target genes.