Johnson Controls T-4002-5012 Thermostat Knob Adjustment KitThermostat Knob Adjustment Kit for Johnson Controls T 4002 5012 thermostats delivers precise, reliable control for your heating system. This knob kit offers a single temperature setting and is designed for use with the item thermostat, providing a straightforward replacement part for compatible Johnson Controls equipment and a dependable thermostat adjustment option. Designed as a practical replacement knob kit, it helps maintain temperature control

supporting efficient furnace control and extended system life

it features durable construction and resistance to heat and humidity in condenser environments

Air Conditioner Air Cleaner keeps your cooling system running at peak efficiency by trapping dust

APC1330H41

It works with the S21

it supports quick checks of pressure integrity and helps technicians document results for quality control

and brass construction for durability in demanding steam service

Applicable Standard: Mil Spec A-A-60001 Type V

It’s suitable for a wide range of settings—from single-family homes to smaller office buildings—where compliant backflow protection is essential

Included components— Fyrite Classic (0–20% CO2)

Its selectable purge and recycle features improve ignition reliability

it restores proper airflow and supports consistent furnace performance