Vaillant (Before 2012 Version) Diverter Valve 178978
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Technical details
Vaillant (Before 2012 Version) Diverter Valve 178978
Product Overview
The Vaillant (Before 2012 Version) Diverter Valve 178978 is a critical component designed for specific Vaillant heating systems. This Diverter Valve mechanically directs hot water to either the radiators (heating) or the taps (hot water), ensuring demand priority. properly functioning components are vital for the energy efficiency and safety of your boiler.
This part may be available in New, Refurbished, or Compatible conditions. Please select your desired option from the dropdown menu above. All refurbished parts are professionally tested to ensure reliability.
Technical Insight & Common Failure Symptoms
Based on service data: Common signs include poor heating performance, fluctuating water temperatures Vaillant Diverter Valve Repair Kit Cartridge 0020020015 178978 0020132682. Position of diverter valve (when accessories are fitted). 0 = Heating; 100 protection tap has disengaged Faults in the gas valve, wrong gas setting
Replacing this part often resolves the following issues:
- Restores reliable system operation and eliminates fault codes.
- Resolves specific failure symptoms such as component malfunction.
- Ensures safety compliance and efficient boiler performance.
Compatibility
This part (MPN: 178978) is designed for models within the Vaillant range. Please strictly verify the part number against your boiler's technical manual before ordering to guarantee fitment.
Safety Advice: Boiler parts involve gas, water, and electricity. Installation must be carried out by a Gas Safe registered engineer.
