A freezer room is a walk-in room that holds frozen food below freezing. A cold room is a walk-in room that holds chilled food above freezing. Both are insulated and cooled by a refrigeration system, and they differ in the temperature each is set to hold, the plant that holds it and how the room is built to keep it. Climate Flow Limited installs and services both across London, Oxfordshire and surrounding areas.
Chilled stock goes in a cold room and frozen stock goes in a freezer room. This guide explains the differences, what to check before you choose, and the maintenance a freezer room needs. For the build itself, see our cold rooms and freezer rooms installation page.
What temperature does each room hold?
Chilled food must be kept at 8°C or below (GOV.UK, chilling and freezing). Guidance for fridges is to set them to 5°C or below, so that food stays cold enough even if the temperature changes. A cold room is set for chilled food within those limits.
A freezer room holds food below freezing. The set point is chosen for the product that goes in, so the engineer confirms what the room must hold before the plant is sized. A room that cannot hold its set point is a reason to call an engineer.
How are the walls, floor and doors built?
Both rooms are usually built from insulated panels. A freezer room works against a larger temperature difference between inside and outside, so its panels, insulation and fixings are specified for that load.
The floor needs as much attention as the walls. Ask the engineer how the floor and the ground beneath a freezer room are protected.
Doors on these rooms let warm air in each time they open, and that warm air can leave ice on the floor or in the doorway. Door seals and hinges are the parts to check first when ice appears there.
What refrigeration plant runs each room?
Both rooms use the same main parts. The condensing unit, outside, holds the compressor and the condenser that rejects heat. The evaporator, inside, is the cold coil that takes heat out of the air. A valve feeds refrigerant to the evaporator, and a controller sets the temperature and the defrost cycle. A freezer room runs colder, so its refrigerant flow and defrost settings are chosen for a lower temperature. Our commercial refrigeration services cover the plant for both types of room.
What does the law ask of the refrigeration work?
Refrigeration circuits that contain F gases are controlled by UK rules, and the people who work on them need the right qualifications. Companies must hold certification to work with F gas (GOV.UK, F gas in refrigeration and air conditioning). Climate Flow Limited is F-Gas certified.
Leak checks are part of the upkeep. For equipment holding 5 to less than 50 tonnes of carbon dioxide equivalent, a leak check is due at least once every 12 months. Responsibility for stopping leaks is shared between the user of the equipment and the technician who services it (GOV.UK, checking F gas equipment for leaks).
What should a business check before choosing a freezer room?
Check the product, the floor, the door route, the space outside and who services the plant before the order is placed.
- The product to be stored, and the temperature it needs, so the set point is known before the plant is chosen.
- The ground and floor under the room, and how they are protected.
- The door route and how often the door opens, since each opening lets warm air in.
- Space for the condensing unit outside, with air able to reach it.
- Who carries out the service visits and leak checks once the room is running.
What maintenance does a freezer room need?
Keep the door seals intact and the door closing fully. A damaged seal lets warm air in every time the door shuts. Check the evaporator for ice, and ask the engineer to check the defrost settings, because a room that defrosts poorly runs warm or ices up. Our guide to cold room defrost cycles explains the controller settings.
Planned preventive maintenance (PPM) is a scheduled visit that checks the system before it fails. On a freezer it covers the condensing unit, the evaporator, the controller and the door, and the leak checks that the F gas rules require. Repair and maintenance work is set out on our refrigeration repair and maintenance page.
When to call an engineer
Call an engineer before stock is at risk if the display reads above its set point, the room does not recover after the door opens, ice builds up, a door does not seal or the controller shows an alarm.
Keep the door shut while you wait for the engineer.
This guide is general information, not a survey or a quote for your site; every system is different, so an engineer needs to see yours before any work is priced.