Complete no cool call. Customer states ever since the last tech re wired the system to utilize the heat pump instead of only the electric heat strips for better efficiency they have smelled a bad smell for the first few seconds of startup then the smell dissipates. They do not want to utilize the heat pump just the electrical heat strips. I showed them how to only use electric heat strips and they were happy with that. I did explain to them that the smell is mainly caused by a dirty evaporator coil. There coil needs to be cleaned. A uv light also should be installed. They understand this and will get it done possibly in the future. Service call fee collected. * we will need to send the customer a paper copy of the invoice.