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RMC HPNR503 High-Pressure Expansion Non-Return Valve - 15mm - 1400kPa
RMC HPNR503 High-Pressure Expansion Non-Return Valve - 15mm - 1400kPa
John Guest

RMC HPNR503 High-Pressure Expansion Non-Return Valve 15mm · 1400kPa

$175
Short delay, none in stock.
Order now for estimated dispatch on 7th Oct 2026.

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Postage Australia Wide

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Description

RMC HPNR503 is a 15 mm high pressure expansion non-return valve for coil type heat exchange water heaters. It combines non-return and pressure relief functions in one valve.

The non-return function helps prevent hot water backflow into the mains supply, while the relief valve protects the coil from over-pressure. It is intended for installation on the cold/inlet supply of a compatible water heater.

Features

  • Combination non-return and pressure relief valve for heat exchange water heaters.
  • Directs expanded water back to the storage tank rather than dumping it to waste.
  • Suitable for horizontal or vertical installation.
  • Dezincification-resistant brass construction for potable water applications.
  • Sealed spring cavity helps prevent the spring seizing due to calcification.
  • 1 year warranty.

Specifications

  • Manufacturer Part Number: HPNRX1503
  • Brand: John Guest
  • Model: HPNR503
  • Type: HPNR unrestricted high pressure expansion non-return valve
  • Nominal size: 15 mm
  • Pressure setting: 1400 kPa
  • Maximum temperature: 99 °C
  • Kilowatt capacity: 10 kW
  • Inlet thread: DN15Cu 1/2
  • Coil connection: G3/8 female
  • Static tank connection: G1/2 female
  • Dimensions: 119 mm high x 53 mm wide
  • Body material: DZR forged brass
  • Spring material: stainless steel
  • O-ring material: nitrile
  • Seal material: silicon
  • Check valve materials: EPDM, POM and stainless steel
  • Approval: AS 1357.1, WaterMark LIC WMKA 0938

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RMC HPNR503 High-Pressure Expansion Non-Return Valve - 15mm - 1400kPa

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Ask us before ordering. If you buy the part we confirm for your setup and our recommendation is wrong, we’ll cover return postage and delivery of the correct replacement.

If we can’t supply a suitable replacement, we’ll refund the part.

We’ll explain any difference in the replacement part’s price before arranging the swap.

The promise applies to the setup and details we checked. If we can’t confirm suitability, we’ll say so before you buy. This is additional to your existing consumer rights.

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