The main purpose of this Vaillant WH40 low-loss header is to maintain the correct flow of water through the boiler and allow a constant temperature supply of water to reach multiple heating circuits downstream of the low-loss header connection. Features: Maintains correct flow of water through the boiler. Aids in providing a constant temperature supply of water to reach multiple heating circuits downstream of the low-loss header connection. Suitable for new clean systems up to 70kW net input.
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