You might be surprised to know the answer!
Short answer? You can send back a newly installed piece of equipment IF you have a good reason.
Let me first say, it’s important to use this as the “nuclear option”. Sending a new instrument back to the OEM is not always as simple as telling them to take it off the bench and issue a full refund. That being said, it is within your right to do so.
Recently I had a friend go through several weeks of downtime with a newly installed instrument. At first, it seemed like familiarization issues. Then it seemed like method issues. After three more visits from the Field Service Team, it became apparent the system was not functioning properly and was costing his company money every day it was not working. Not to mention, his customers were also being affected!
After consulting with me and the OEM, he made the decision to send the system back. Luckily he had the old system in storage and could get it up on the bench (something else to consider, should you find yourself in this situation).
Hold the OEMs responsible for the quality of their instrumentation. Do not feel you just have to deal with an issue. I have seen too many companies with unused systems in their labs because no one could use them or they were constantly down and unreliable.
Beyond anything else, understand that you are dealing with fellow human beings. Treating everyone with respect and kindness can go a long way in creating opportunities for better outcomes.