REFRIGERANT INVENTORY: WHY AND HOW

OVERVIEW - WHY

A refrigerant inventory is similar to a typical greenhouse gas inventory, but focuses on air conditioning and refrigeration equipment and the refrigerant gases inside. Along with refrigerant information, facilities managers can also collect equipment serial and model numbers that can be useful for organization and procurement.

Inventories have key benefits for procurement and maintenance strategies, environmental compliance, and environmental impact reduction. Having better data about refrigerants in facilities also allow decision-makers to answer important questions. These include:

What proportion of HVAC equipment in a facility uses regulated refrigerants such as HFC, HCFC, and CFC?
Where are the largest sources of refrigerant emissions on campus?
Where is aging/inefficient equipment located?
What is annual climate impact from refrigerant leakage?

READING REFRIGERATOR NAMEPLATES

The refrigerator "nameplate" is the sticker on the back panel or the interior of a refrigerator that lists important information for facility managers to know. Typically, these nameplates list: manufacturer, serial number, model number, energy usage information, refrigerant charge size, and refrigerant type. These nameplates are also very small. It can be helpful to take pictures of the nameplate and zoom in on the image to input these data accurately.

CONDUCTING THE INVENTORY - TIPS AND TRICKS

This section is in large part thanks to Dan Smith, Energy Manager at Bard College.

Inventories can be daunting with many buildings, lots of equipment, and the time required to categorize and input inventory data.

Contact building managers, facilities supervisors, and refrigerant technicians to locate pre-existing inventories and documentation. These documents may include maintenance logs, building lists, and construction drawings. Construction drawings and equipment schedules can help facilities staff save time when looking for HVAC equipment in a building.
Divide and conquer among facilities staff: split up buildings and determine roles. In our experience, two well-trained staff inventoried 14 dining halls in about eight hours. The data entry for these dining halls also required about eight hours.
Scope and prioritize: determine boundary and proximity, and size of capital assets. Focus on the "low-hanging fruit" first, such as large equipment known to use high-Global Warming Potential refrigerants. This equipment includes process cooling, chillers, central air conditioning, and compressor racks (often used in supermarkets or dining halls).
Take pictures and document your steps. Dan Smith, Bard College's inventory leader, recommends taking three different pictures for each HVAC unit. First, take an establishing shot of the building in which the unit is located. Second, take an establishing shot of the equipment and its location in the building. Third, take a zoomed-in shot of the refrigerator nameplate. Taking good pictures is incredibly helpful when entering data.
Filling gaps in incomplete data: occasionally, data will be missing, incomplete, or unreadable on the refrigerator nameplate. In these cases, look for notes from your refrigerant technician or use the serial and model number on the nameplate to search for the data online. You can often find missing data in manuals, brochures, or cutsheets. You can also use your intuition for HVAC equipment to fill in gaps, based on what you know similar equipment to have.

HOW TO USE THE DATA

After beginning your inventory, you can begin to process your data to find useful metrics such as carbon dioxide equivalent emissions from refrigerant leakage. Consolidating data in a spreadsheet can also be useful in identifying where old and inefficient equipment is located. Using Microsoft Excel or a similar program is most useful.

Below are useful resources for your calculations.

GWP-20 numbers for different refrigerants

Calculating refrigerant leak rate