@stolidmind,
Make sure electrical connections are intact and look for and note any evidence of damage, leak, valves in wrong position, inordinate noise, strange smell, or alarm indications on the equipment and associated plumbing. Document these, and if you have not discovered a condition that you could correct yourself, call the dealer and ask for a phone interview with a responsible technician. If you don’t feel you can trust the technician, document that and ask to speak with the manager or owner. Be sure to keep detailed notes of your phone conversation, for these become legal documents admissible in court, in the event you accelerate the dispute to the courts.