Alpha Heat Exchanger Domestic Hot Water 1.022221

The Alpha 1.022221 is a domestic hot water heat exchanger for Alpha combination boilers in the CD28 range. It sits on the hot water circuit and transfers heat from the boiler's primary water into the mains-fed domestic supply, so the plate stack is what actually heats the water drawn at the tap. Because the waterways inside a DHW heat exchanger are narrow, scale and sludge build-up make this a routine replacement item on these appliances.

• Hot water runs lukewarm or cold while the central heating continues to work normally.
• The hot water temperature fluctuates or falls away as the tap is left running.
• Hot water flow rate at the outlet is noticeably lower than the cold supply.
• Kettling, banging or whistling from the boiler when hot water is demanded.
• Water weeping from the plate stack, or staining and scale deposits around the exchanger.

• Check the GC number on the appliance data badge against the compatibility table above; the CD28C and CD28X variants carry different GC numbers.
• Confirm the exact model and whether the boiler is set up for natural gas or LPG.
• Inspect the seals and gaskets on the hot water circuit before refitting and renew any that are perished.
• This part is fitted to a gas appliance; installation must be carried out by a Gas Safe registered engineer.