Glow-worm HVAC Repair Cost (UK, 2026)
Estimates reviewed July 2026 · appliance-repair figures maintained by a licensed appliance technician.
Glow-worm HVAC repairs typically run £30–£3,500, depending on the HVAC system, the problem, and your local labour costs. Glow-worm is a mainstream brand — its parts sit at the mainstream baseline. Every figure is an Estimated range in pounds, never a fake precise number. Reviewed July 2026.
Glow-worm repair cost by HVAC Estimated
These ranges apply Glow-worm's parts tier (1.00× the mainstream baseline) to the parts portion only — labour is unchanged and localizes to your area. Tap an HVAC system for its full problem-by-problem breakdown and the localizer.
| HVAC | Estimated Glow-worm range |
|---|---|
| Glow-worm heat pump repair | £50–£3,500 |
| Glow-worm boiler repair | £30–£750 |
| Glow-worm thermostat & controls repair | £40–£520 |
Base: 3 published national repair-cost guides (retrieved 2026-07) · full source registry on the methodology page · UK national base range (ONS ASHE 2025 SOC 5315) · Reviewed July 2026 · Estimated
What changes a Glow-worm repair bill
- Brand tier — Vaillant Group's volume UK brand since the Hepworth acquisition; it shares Vaillant technology but is stocked and priced as a mainstream line. Its listed main PCBs — Flexicom/Ultracom BMU £232.80, Xi-range £261.60, Ultracom £218.40, all incl VAT, plus a diverter valve at £159.60 — are the observed price range that anchors the 1.0 baseline for this whole index, midpoint £240.00
- Parts vs labour — the brand and tier shift the parts price; labour tracks your area's wage index, not the brand.
- The specific fault — a sensor, seal, or valve is far cheaper than a compressor, motor, or control board.
- DIY vs professional — Some Glow-worm faults (filters, seals, hoses) are DIY-feasible for confident owners; sealed-system and control-board work is a professional job.
Glow-worm error & fault codes
When a Glow-worm HVAC system shows a fault code, the diagnosis — and the price — gets specific. The most looked-up Glow-worm codes:
Glow Worm F.91 Glow Worm F.22 Glow Worm F.28 Glow Worm F.29 Glow Worm F.78 Glow Worm F.89 Glow Worm F02 Glow Worm F03 Glow Worm F79 Glow Worm F.13 Glow Worm F.00 Glow Worm F.01 +34 more →
Common Glow-worm problems
Glow-worm boilers present with the usual class faults: falling pressure, ignition lockout, condensate blockage, and hot-water failure from a diverter valve or plate heat exchanger. Fault codes generally point to sensors, the fan or the pump rather than to the primary heat exchanger. Noise and kettling complaints in hard-water areas are scale-related.
Is Glow-worm expensive to repair?
Glow-worm is the value-positioned brand within the Vaillant Group (acquired 2001), sharing group engineering while sitting below Vaillant in specification and warranty tier. Its repair profile tracks the general UK boiler class. It has also launched an air-source heat pump range with matching cylinders and controls. Spares are widely available through UK merchants and the Vaillant Group parts channel, and some components cross-reference to Vaillant equivalents, which helps sourcing. Common wear parts are routinely stocked. PCBs and gas valves are genuine-channel items.
Estimated labour-cost-localized ranges — see the methodology for the localization method and named sources.
Reviewed by a Red Seal–certified appliance technician who also holds a Technical Safety BC gas ticket (Gas-C) and an ODS/halocarbon refrigerant ticket (CFC/HCFC/HFC).