DIAGNOSIS No, that's far too long. The most common cause is insufficient heat or too much liquid/food volume.
FIX Start with high heat, uncovered, until the contents come to a full, rolling boil. Only then lock the lid in place with the regulator on. Keep the heat on high until the regulator begins to rock/jiggle steadily (this should take 5-15 minutes max). Then reduce heat.
IF THAT DIDN'T WORK Check that you're using the minimum required liquid (usually 1-2 cups for this size) and not overfilling the pot (never above 2/3 full). Too much mass (e.g., a huge frozen roast) or too little liquid will prevent steam generation.
HEADS UP Using a burner that's too small for the pot's wide base can drastically increase heat-up time. Ensure the burner size matches the pot's bottom diameter for efficient heat transfer.