Article reference KA-02380
The Series A to G Quantum Storage Heaters have a separate boost element near the bottom grill which may glow red if "Boost" is selected. It is normal to see the element glow red behind the air outlet grill, when Boost is selected (or if Autoboost was enabled).
Note: The later produced Series G5 to G14 & Series Z & Y Quantum storage heaters do not have a separate boost element, as the bottom storage element in the core serves dual purpose and is used for the boost feature if Boost is selected.
Applicable Models:
QM070, QM100, QM125, QM150