Heat checkup on 2 trane we installed. Both systems working properly at this time but airflow and ductwork are a concern. Only return is upstairs and the downstairs return was replaced with cabinets so I'm unsure where its pulling from. Advised customer to get with contractor about registers and possible fix. Recommendations are for drain line upgrades to fix lack of fall which will be an issue when the ac runs and adding returns upstairs leaving the return chase for the downstairs only. Can confirm heat is running atthis time