Do I have to go to the office in this heat?
Article

While Switzerland does not prescribe fixed maximum temperatures, protective measures in the workplace are mandatory.
If you didn't get anywhere in the pay talk, just keep at it. Explain why you are unhappy with the outcome and ask for another meeting in the near future.
Try to find out why the negotiation failed and prepare for the second round. If this does not lead to success either, the signs may point to departure: start looking for a new job.