Ultra Low Cold Room Manufacturer in Pune
Ultra-low temperature cold rooms
An ultra-low temperature (ULT) cold room is a walk-in store that holds −40 °C to −80 °C. It is used for biological samples, some pharma materials, sushi-grade tuna and low-temperature testing. These products need a colder, more stable store than a −18 °C freezer. Falcon Refrigeration designs, makes and installs ULT rooms in Pune and across Maharashtra.
A walk-in room makes sense when the stock is too large for cabinet freezers. It also lets staff load racks or pallets directly. Each room is built for one temperature band and one product type.
What is stored at ultra-low temperatures
The right set point comes from the product owner's storage rules, not from the room builder. These are common uses and the temperatures usually quoted.
- Biological samples: DNA, RNA, cells and tissue for long-term storage, commonly at about −80 °C.
- Pharma and biotech materials: some active ingredients, enzymes and biologics. Labels may say −20 °C, −40 °C or −70 °C and colder.
- Vaccines: most need +2 to +8 °C, but a few frozen vaccines need much colder storage. Always follow the product label.
- Blood plasma: usually kept at −30 °C or colder. Blood banks follow their own regulatory limits.
- Tuna and high-value seafood: sushi-grade tuna is held at about −60 °C to keep its colour and texture.
- Testing: automotive and electronics firms test parts at −40 °C and below.
If you only need −18 to −25 °C, a standard freezer room costs less to build and run. See our page on cold rooms across Maharashtra for the usual temperature classes.
How the refrigeration reaches −80 °C
A normal single-stage system works well down to about −40 °C. Below that, the compressor has to lift heat over too large a pressure ratio. So colder rooms use one of two designs.
Two-stage compression
Two compressors share the lift. The low stage pulls the gas from the evaporator, and the high stage pushes it to the condenser. This design is common for rooms from about −40 °C to −55 °C.
Cascade system
For −60 °C to −80 °C, two separate refrigeration circuits are linked by a heat exchanger. The low circuit uses a refrigerant suited to very low temperatures, such as R23 or R508B. The high circuit uses a common refrigerant, such as R404A or R449A, and rejects heat outside.
The outdoor condensing unit must be sized for Pune's summer peak. Many owners also ask for a standby circuit, so one failure does not warm the room.
Insulation, doors and floor
At −80 °C, the difference from a 35 °C ambient is over 110 °C. Small gaps that a chiller can tolerate become serious leaks.
Panels
Walls and ceiling use thick PUF panels with foam density of about 40 ± 2 kg/m³. Typical thickness is 150–200 mm, depending on temperature and site. Every joint is sealed so moist air cannot reach the foam and freeze inside it.
Doors
ULT rooms use thick insulated cold room doors with a heated frame and double gaskets. A pressure relief port stops the walls flexing when the air inside cools. An inside release handle and an alarm button protect staff.
Floor
The floor is fully insulated. On a ground slab it also needs heating or a ventilated base, so the ground below does not freeze and heave.
Anteroom
Many ULT rooms have a small anteroom held at around −20 °C or +2 to +8 °C. Staff pass through it, so less warm, moist air reaches the main room. It also cuts frost on the evaporator.
Typical specifications (confirm for your project)
These are general industry ranges, not fixed values. We confirm each item after the heat load calculation and your product requirements.
| Item | Typical range |
|---|---|
| Room temperature | −40 °C to −80 °C, one set point per room |
| Temperature stability | Commonly ±2 to ±3 °C at the control sensor |
| Refrigeration system | Two-stage to about −55 °C; cascade for −60 to −80 °C |
| Refrigerants | High stage R404A or R449A; low stage R23 or R508B |
| Panel insulation | PUF, 150–200 mm, density about 40 ± 2 kg/m³ |
| Panel skins | Pre-painted GI or stainless steel |
| Floor | Insulated, with heating or ventilation on ground slabs |
| Door | Insulated hinged door, heated frame, pressure relief port |
| Defrost | Electric or hot gas, timed or on demand |
| Monitoring | Dual sensors, data logger, local and remote alarms |
| Backup | Standby circuit and generator supply, where specified |
Monitoring, alarms and backup
A ULT room usually holds high-value stock that cannot be replaced. Monitoring and backup matter as much as the cooling itself.
- Two independent temperature sensors, one for control and one for the alarm.
- A data logger that keeps temperature records for audits.
- High temperature, door-open and power-failure alarms, with SMS or app alerts.
- A standby refrigeration circuit that starts if the main one fails.
- A generator supply sized for the compressor starting load.
Staff working inside need insulated clothing and short work periods. Plan the racking so items can be found and picked quickly. If the stock must be frozen fast before storage, pair the room with a blast freezer.
Frequently asked questions
What temperature range can an ultra-low cold room hold?
Walk-in ULT rooms commonly hold between −40 °C and −80 °C. Rooms down to about −55 °C usually use two-stage compression. Colder rooms, down to −80 °C, use a cascade system with two linked circuits. Each room is designed for one set point, chosen from the stored product's requirements.
Why not use several ULT cabinet freezers instead?
Cabinets suit small volumes and single labs. A walk-in room is better when stock fills many cabinets or arrives on racks or pallets. One room also means one set of alarms and records. However, cabinets keep running separately, so one failure affects less stock.
How thick are the panels in a ULT room?
Panels are usually 150–200 mm thick, with PUF at about 40 ± 2 kg/m³. The exact thickness depends on the set point, the ambient temperature and whether the room is indoors. The floor is also insulated. We confirm the panel thickness after calculating the heat load.
What happens if the refrigeration fails?
The alarm system warns staff as soon as the temperature starts to rise. A well-sealed room warms slowly if the door stays closed. Many owners specify a standby refrigeration circuit and a generator. Together, these keep the room cold during a breakdown or power cut.