Gas boiler repair, maintenance and annual inspection in Modderfontein and the wider Johannesburg area. Same-day response for commercial and industrial plant across Gauteng.
Local Service
Our certified technicians service gas boilers across Modderfontein and the Johannesburg region — from office building hydronic heating to food & beverage process hot water. We carry common burner spares, safety valves and controls for major brands including Bosch, Viessmann, Loos, Cleaver-Brooks. Annual inspection, combustion analysis, tube cleaning and emergency breakdown response are all available in Modderfontein.
Brands
Our Service
Troubleshooting
Likely causes
What to check
Check the flow and return temperatures, gas inlet pressure, and whether the pump is running at full flow. Compare cycle times against the heating curve.
When to call us
If cycles are under 5 minutes the heat exchanger will scale prematurely and the gas valve will wear. Book a combustion analysis and flow rate check.
Likely causes
What to check
Measure flue gas temperature and CO₂ against manufacturer data. Check return water temperature is below 55 °C for condensing mode.
When to call us
If flue temperature is above 80 °C on a condensing boiler, you're wasting fuel and the heat exchanger needs descaling. We carry out chemical descaling on site.
Likely causes
What to check
Reset and observe the ignition sequence. Check the condensate trap is draining, the air intake is clear, and the flame sensor is clean.
When to call us
If the boiler won't fire after a condensate drain and sensor clean, the gas valve or ignition system needs professional diagnosis — don't keep resetting.
Likely causes
What to check
Check system pressure (1–1.5 bar cold), bleed radiators, and listen for pump cavitation. A rumbling or banging sound usually means scale.
When to call us
Kettling damages the heat exchanger. Book a chemical descale before a pinhole leak develops — heat exchanger replacement is the most expensive repair on a gas boiler.
FAQ
Annually for commercial and industrial plant. High-utilisation installations (hospitals, hotels, continuous process) should have a six-monthly combustion check. The annual service includes flue gas analysis, heat exchanger inspection and safety device testing.
Yes — our technicians are certified for natural gas and LPG boiler work, including commissioning, and we issue a Certificate of Conformity (CoC) on any gas installation or modification as required by SAQCC Gas.
Often yes — a combustion tune-up, heat exchanger descale and controls upgrade (weather compensation, modulating burners) can recover 5–15% efficiency. On condensing boilers we ensure the return temperature allows condensing.
Both. We handle conventional atmospheric and forced-draught boilers as well as modern condensing units, including the condensate neutralisation system and stainless steel heat exchanger inspection.
Same-day across Gauteng for heating-critical sites like hospitals and hotels. We carry common gas valves, ignition components and sensors for major brands.
Yes — annual planned maintenance with scheduled visits, priority breakdown response, and a combustion report after every service. Contract clients get same-day dispatch.
Nearby Areas
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