I'm having a replacement heatpump installed with new matching airhandler. The HVAC contractor told me that it is their practice to install a new drip pan under the unit with an emergency float shut off should the water in the pan get too high. He said they don't as a rule install a secondary drain from the pan itself.
I've checked my present installation and the pan does have a pvc drain line coming out of it in addition to an emergency float shutoff in the pan. The secondary emergency pan drain ties back into the main drip line just before the cleanout tee.
I've got two questions. First...is it standard practice to forgo the actual second drain from the pan itself and just rely on the float switch to stop the unit should the primary drip line coming from the coil have a problem?
Second... if indeed the practice is to actually have a second pvc drip line coming from the pan itself(and an emergency float switch) wouldn't it make sense that it not tie into the first drip line and be an independent line run out of the house...maybe next the present drip line.
Any thought would would be appreciated.