Guide
Cold rooms and air-conditioning: what actually keeps them working
A practical guide for shop owners, restaurant kitchens, butchers, schools and homeowners in Alberton and the East Rand who would rather service equipment than replace stock.
How a cold room holds temperature
A cold room is a closed box, an evaporator that pulls heat out of the air, a condensing unit outside that dumps that heat, and insulation that stops it leaking back in. Every part has to hold its own end. A clean evaporator with a blocked condenser will run constantly and still not hold temperature. A perfect plant in a room with a damaged panel and a worn door seal will ice up at the door every night. When a cold room "isn't working", the fault is usually one of three things: airflow over the evaporator, heat rejection at the condenser, or the seal on the room itself.
Why freezer rooms fail differently
Freezer rooms sit well below zero, so moisture behaves differently. Ice builds on coils, drains freeze, and defrost cycles do the quiet work that keeps everything moving. When a defrost timer or heater fails, the room still reaches temperature for a few days — then airflow closes up and the whole unit works twice as hard for half the result. That is why frozen stock and a healthy-looking compressor can still mean a room in trouble. Regular defrost checks cost far less than a weekend of lost product.
Servicing intervals that make sense
Commercial refrigeration in Gauteng works in dust and heat, so condensers load up faster than the manual suggests. A working rule: clean and inspect a commercial condensing unit every three to six months, check door seals and drains at the same visit, and pressure-test gas at least once a year. Split air-conditioners need their filters washed monthly in heavy use and a proper service — coil clean, drain flush, gas check — before summer starts. Servicing on that rhythm is cheaper than a single after-hours callout, and far cheaper than a compressor.
Signs to call someone today
Ice on the evaporator or the suction line, water pooling on the floor, a unit that runs without stopping, a breaker that trips when the compressor starts, warm air from a split's indoor unit, or a room that takes noticeably longer to pull down than it did last month. Each of those is a symptom with a specific cause, and each gets more expensive the longer it runs. A compressor that keeps starting against a fault will eventually stop starting at all.
Sizing and installing air-conditioning
Air-conditioning is sized on the room, not on the price list. A unit that is too small runs continuously and never satisfies the space; one that is oversized cools fast, short-cycles and leaves the room clammy. Ceiling height, glazing, roof insulation, the number of people and heat-generating equipment all matter. Then installation decides the rest: pipe lengths within spec, a proper vacuum before charging, a drain with fall, and an outdoor unit with airflow around it. Get the install right and a midwall split will serve a bedroom or office quietly for a decade.
Choosing who works on your equipment
Ask three things: who will actually be on site, what the fault is before the quote, and what happens if it comes back. A technician who diagnoses before quoting is worth more than a cheap callout that becomes a second invoice. Legacy Air works Alberton and the East Rand on exactly that basis — the people who quote are the people who arrive, and the job is either installed, repaired or serviced properly.
Common questions
Cold rooms
How cold should a cold room actually run?
Chiller cold rooms generally sit between 0 °C and 4 °C, depending on what is being stored. Butchery and fresh produce want the cold end; dairy and drinks tolerate slightly higher. What matters more than the number on the controller is that the room pulls down quickly after the door closes and holds steady overnight. A room that creeps up between deliveries has an airflow, gas or insulation problem.
Servicing
How often should commercial refrigeration be serviced?
Every three to six months for a busy kitchen or butchery, and at least twice a year for a shop display unit. Gauteng dust and heat load condensers quickly, and a dirty condenser is the most common reason a unit runs hot and shortens its compressor's life. Each service should cover condenser cleaning, evaporator and drain check, door seals, gas pressures and electrical connections.
Repairs
The cold room runs but isn't getting cold. Can it be repaired?
Usually yes, and it depends on why. Ice on the evaporator, a failed defrost cycle, a blocked drain, a fan that has stopped, low gas from a leak or a failing compressor all look the same from the doorway: the unit runs and the room stays warm. A technician can tell them apart on site with pressures and current draw, which is why we diagnose before quoting rather than guessing at a part.
Air-conditioning
What size air-conditioner do I need for a room?
It is calculated from the room, not picked from a price list. Floor area, ceiling height, window and roof heat, insulation, how many people use the space and any heat-generating equipment all change the load. An undersized unit runs all day and never satisfies the room; an oversized one cools fast, short-cycles and leaves it clammy. Give us the room dimensions and we will size it properly before quoting.
Air-conditioning
Why is my aircon dripping water inside?
Almost always the condensate drain. A blocked drain line, a drain pan sitting without fall, a dirty filter pulling ice onto the coil or a frozen evaporator will all send water into the room instead of outside. It is a service item, not a gas problem, and it gets worse if left — water near electrics and ceilings becomes expensive quickly.