A system including a processor and sensor for installation inside an underground vault. The sensor monitors a parameter inside the vault and sends a monitoring signal to the processor. Based on the monitoring signal, the processor may provide data to a memory for storage and/or control signals to an interface for transmission to an external device located within the vault. The control signals instruct the external device to modify the environment inside the vault. The sensor may be positioned inside an enclosure, which is inside a housing. An air moving device moves air into or out of the enclosure thereby drawing air from the vault into the enclosure before the sensor monitors the parameter. A heat generating component may be positioned inside the housing and when generating heat prevents moisture from condensing therein. The system may include a power unit that draws power from a power source inside the vault.

An access panel assembly and a heating, ventilation, and/or air conditioning (HVAC) system incorporating the access panel assembly are provided. The HVAC system includes a heat exchanger assembly with a first heat exchanger coil and a second heat exchanger coil (e.g., in a V-shaped configuration). The first heat exchanger coil and the second heat exchanger coil each respectively include an exterior surface, an interior surface, a first edge, and a second edge. The access panel assembly is adjacent to the first edge of the first heat exchanger coil and the first edge of the second heat exchanger coil. The access panel assembly is configured to provide access (e.g., for cleaning and/or maintenance) to at least one of: the interior surface of the first heat exchanger coil and the interior surface of the second heat exchanger coil.

A hinge assembly includes a pair of lower mounting brackets, at least two upper hinge leaves, a pair of side brackets coupled to the sidewalls of the ventilation fan lid, each side bracket having at least one third axle hole therethrough, an axle pivotally coupling the upper hinge leaves to the lower mounting brackets. Each lower mounting bracket has a vertically oval-shaped axle hole. Each upper hinge leaf includes a U-shaped mounting member and a hook shaped clamping plate coupled to the U-shaped mounting member through threaded tension bolts. The upper hinge leaf also has a pair of axle holes. The axle extends through the elongated axle holes of the lower mounting bracket vertical flange and through the axle holes of the U-shaped member.

The removable access panel for HVAC closet is configured for use with an HVAC system. The removable access panel for HVAC closet forms an access panel that provides access to the interior of the enclosure that contains the HVAC system. The removable access panel for HVAC closet removably attaches to the enclosure that contains the HVAC system. The removable access panel for HVAC closet is a foraminous structure that allows air to flow into and out of the enclosure that contains the HVAC system. The removable access panel for HVAC closet removably comprises a frame structure and a door structure. The door structure controls access into the enclosure that contains the HVAC system. The frame structure removably attaches the door to the enclosure that contains the HVAC system.