We report on our measurement of the inclusive spectrum of positive pions from the reaction pp→π++X on a CH 2 internal target of the ITEP proton synchrotron at 1.5 GeV/c with a missing mass resolution of about 1 MeV/c2. The goal of our experiment was the search for the hypothetical narrow πNN resonance (0.5\ MeV/c2 width and a mass of 2.06\ GeV/c2) with I(J P P)=even(0−), called d′. We do not see any statistically significant d′-signal. The upper limit for d′ production cross-section in pp-interactions is near 2μb at 84%C.L.