Answer to Question 1
Water protection A weather resistant cabinet along with a water shedding base pan with elevated downflow openings and a perimeter channel prevent water from draining into the ductwork.
Low ambient control (optional) Kits are available that control the condenser head pressure to permit the unit to cool the ambient temperature.
Economizer (optional) An economizer and dry bulb temperature sensor can be supplied for downflow installations. This makes it possible to use outside air for cooling when outdoor temperatures and humidity permit.
Enthalpy control kit (optional) This can be supplied in place of the dry bulb sensor, or two enthalpy controls can be paired to provide differential enthalpy control. Fresh air (25) kit (optional) This kit can be mounted over the horizontal return air openings for downflow requirements. It also can be used on horizontal applications by cutting a hole in the return air duct or in the unit filter access panel.
Fan delay relay kit
Answer to Question 2
Typical types of screws are sheet metal screws, wood screws, and machine screws.
Common structural features
Surface Features on Titan
A properly mounted 12-lead, single channel ECG.
Horizontal stroking across the lower back.
Some obesity genes in the human genome. The green triangles represent single genes in which obesity
Summary of DNA synthesis at a single replication fork