Commercial Kitchen Gas Installers
Cape Town

A commercial kitchen gas system is an engineering problem before it is an installation problem. Get the load calculation and the pipe sizing right and the kitchen runs at full output with every appliance firing. Get them wrong and the symptoms show up months later, always at the worst time: burners that drop off when the fryers recover, ovens that will not hold temperature, a regulator that ices up mid-service.

This page is about the technical side of commercial kitchen LPG — how systems are sized, what the components do, and what separates an installation that works under load from one that only works when it is quiet.

Calculating the Kitchen's Gas Load

Everything downstream depends on this number. The process is straightforward but it has to be done properly:

1. 1List every appliance with its rated input in kW. The data plate is the source, not the catalogue. Data plates also tell you whether the appliance is set for LPG or natural gas.
2. 2Total the connected load. This is the theoretical maximum if everything ran flat out at once.
3. 3Apply a realistic diversity factor. A kitchen almost never runs every burner at full for a sustained period. How much diversity is reasonable depends on the operation — a la carte, banqueting, and continuous fast-food production behave very differently.
4. 4Size the pipework for the resulting flow. Pipe diameter is chosen so that pressure drop across the longest run stays within limits at peak flow.
5. 5Size the storage for the vaporisation rate, not just the volume. This is the step most often skipped, and the cause of the most frustrating faults.

Why Cylinder Count Is Not Just About Refill Frequency

Liquid LPG has to turn into vapour inside the cylinder before it can be used, and that process absorbs heat. Draw gas faster than a cylinder can vaporise it and the cylinder chills, pressure drops, frost forms on the outside, and appliances start underperforming — even though the cylinder is still half full.

The vaporisation rate a cylinder can sustain depends on its wetted surface area, the liquid level and the ambient temperature, all of which means a bank of cylinders is often sized by peak draw rather than by how long you want between deliveries. On the Cape Peninsula, winter mornings are cold enough for this to show up on marginally sized banks that were fine through summer. For sustained high draw, the answer is more cylinders in the bank, a larger vessel, or a vaporiser.

Kitchen Equipment and What It Demands

• Open-burner ranges and target tops — moderate individual draw, but six or eight burners add up quickly.
• Wok and stock pot burners — the highest single draw on most kitchen lines by a wide margin. One added wok burner can push a system past its design capacity on its own.
• Deep fryers — high draw during recovery after a basket drops in, then low draw while holding temperature, producing a spiky demand pattern.
• Char grills and salamanders — sustained rather than spiky, running for the whole service.
• Combi and convection ovens — steady moderate draw, but often several units in a production kitchen.
• Deck and pizza ovens — high initial draw while coming up to temperature, then cycling.
• Bratt pans and boiling pans — high sustained draw, common in central production kitchens.
• Bains-marie and holding equipment — low draw, but they run continuously.

The pattern of demand matters as much as the total, because a system sized on averages will fail during the fifteen minutes when everything peaks together.

Regulators, Manifolds and Changeover Systems

The hardware between the cylinders and the kitchen does more than reduce pressure:

• First stage regulator — drops cylinder pressure to an intermediate pressure for the run to the building. Cylinder pressure varies with temperature, so this stage removes that variability from the rest of the system.
• Second stage regulator — drops intermediate pressure to appliance operating pressure close to the point of use, which keeps appliance pressure stable regardless of what is happening upstream.
• Manifold — connects multiple cylinders together as a single supply. Pigtails, non-return valves and a header make up the assembly.
• Automatic changeover valve — runs the kitchen from one bank of cylinders while holding the second bank in reserve, then switches over automatically when the duty bank empties. An indicator shows which bank is in service so empties can be swapped without interrupting supply. For a kitchen that trades every night, this is usually worth doing.
• Overpressure protection and relief — protects downstream pipework and appliances if a regulator fails.
• Line isolation valves — at the building entry, at the start of the kitchen line and at each appliance.

Two-stage regulation is the usual arrangement for a commercial kitchen with any meaningful pipe run, because it keeps appliance pressure steady when the demand pattern is spiky.

Gas Cages and Cylinder Storage

A gas cage does three jobs: it keeps the cylinders secure, it keeps them ventilated, and it keeps them separated from ignition sources and from the building. A commercial kitchen cage is typically a welded steel mesh enclosure with a lockable gate, a solid base, open sides for cross-ventilation, and a roof only where it does not restrict airflow.

• Cylinders stand upright and are secured against falling
• The base is level and non-combustible, with drainage that does not lead to a low-lying trap
• Ventilation at low level matters most, because leaked LPG sinks
• No electrical equipment, switchgear or ignition sources inside or immediately adjacent
• Warning signage and no-smoking signage on the enclosure
• Bollards or barriers where vehicles, trolleys or deliveries pass close by
• Clear access for the delivery vehicle and for cylinder handling

Sizing the cage for the eventual cylinder count rather than the current one is worth doing at the outset, because extending a cage later usually costs more than building it slightly larger the first time.

Safety Equipment on the Kitchen Side

• Emergency shut-off — a clearly marked manual isolation point on the escape route out of the kitchen, so staff shut the gas off on their way out rather than moving toward the equipment.
• Gas interlock — ties the gas supply to the extraction system so gas cannot be established with the canopy off. Increasingly specified on new commercial kitchen fit-outs.
• Gas detection — low-level detector heads suited to LPG, since the gas settles rather than rises. Positioning is the whole point: a head mounted high will not detect an LPG leak in time to be useful.
• Solenoid valve — the component the interlock or detection system actually operates to cut supply.
• Appliance isolation cocks — one per appliance, accessible without moving the equipment.
• Flexible connectors with restraint — on equipment that gets pulled out for cleaning, so the connector is protected from strain.

New Fit-Out Versus Retrofitting an Existing Kitchen

In a new fit-out, gas is designed alongside the kitchen layout, so drops land where the equipment actually goes and the pipe route is decided before the ceilings close. In an existing kitchen the constraints run the other way: the equipment is already in place, the pipe route has to work around what is there, and much of the work happens outside trading hours.

Retrofits also come with a survey question that new builds do not have — is the existing pipework sound, is it correctly sized for the new load, and does it test clean? Reusing existing pipework saves money when the answer to all three is yes. It creates problems when the pipe is reused simply because it is there. Pipe sizing is covered in more detail on the commercial gas pipeline installers Cape Town page.

Testing, Commissioning and Certification

Commissioning a commercial kitchen line is not a single test:

• Strength and tightness testing of the pipework before appliances are connected
• Purging air from the system so appliances light cleanly
• Working pressure checked at the furthest appliance with the system under load
• Each appliance lit, flame picture checked and burner pressure verified
• Isolation valves, changeover and any interlock or detection proven
• Certification issued and handed over with the appliance schedule

The pressure check under load is the one that gets skipped most often, and it is the one that would have caught the undersized pipe before the kitchen opened.

Commercial Kitchen Gas Installation Costs in Cape Town

What determines the number on the quote:

To get quotes you can compare directly, supply the appliance schedule with rated inputs, a rough kitchen layout showing where each machine sits, and a photo of the intended storage position.

Where Kitchen Gas Work Connects to the Rest of the System

Working out what your kitchen actually needs? Get quotes from commercial gas installers in Cape Town and have the load calculation done before the pipework is specified.

Commercial Kitchen Gas Installers FAQs