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Bronze expansion tank gauge with 12 in glass tube and two guard rods

Apollo

Apollo 2070400 Expansion Tank Gauge 1/2 in Bronze

SKU CH-J0WW-9NM61

Bronze expansion-tank gauge with 12 in glass, 13 1/4 in centers, 300 psig and 350 °F ratings, 1/2 in NPT connection and EPDM gaskets

  • Bronze body resists corrosion in hydronic systems
  • 300 psig rating handles high-pressure boiler loops
  • 350 °F maximum temperature suits steam applications
  • 12 in glass gives clear water-level view
  • CRN registration meets Canadian pressure-vessel code

Expansion Tank Gauge 1/2 in Bronze

The Apollo 2070400 expansion tank gauge is a bronze-bodied sight glass for monitoring liquid level in hydronic or plumbing systems. It uses a 5/8 in diameter gauge glass that is 12 in long with a 13 1/4 in center-to-center length. The unit connects via 1/2 in NPT threads and is rated for 300 psig maximum operating pressure and 350 degrees F maximum media temperature.

Installers needing CRN-registered bronze gauges

This gauge suits technicians who require a CRN-registered bronze sight glass with EPDM gaskets and needle drain valves for hot water or compatible fluid service. It is not intended for applications exceeding the stated pressure or temperature limits, nor for media incompatible with bronze, EPDM, or glass components. Buyers needing different connection sizes, materials, or higher ratings should look at alternative models.

Straightforward NPT installation with two guard rods

The gauge threads directly onto 1/2 in NPT fittings and includes two guard rods to protect the glass tube during service. EPDM gaskets seal the connections, while the needle drain valve allows controlled venting or sampling. Common issues include glass breakage from overtightening or impact, gasket degradation if media temperature exceeds 350 degrees F, and leakage if pipe threads are not properly sealed.

Highlights

  • Bronze body resists corrosion in hydronic systems
  • 300 psig rating handles high-pressure boiler loops
  • 350 °F maximum temperature suits steam applications
  • 12 in glass gives clear water-level view
  • CRN registration meets Canadian pressure-vessel code

Specifications

BrandAPOLLO VALVES

Questions about this item

What pipe size must my system have to thread this 1/2 in NPT gauge directly?

The gauge connects to a 1/2 in NPT fitting, so your expansion tank or piping must provide a matching 1/2 in male or female NPT thread.

Will the bronze body and EPDM gasket hold up if my boiler runs near 350 °F and 300 psig?

Yes, the gauge is rated for a maximum media temperature of 350 °F and a maximum operating pressure of 300 psig, with a bronze body and EPDM gasket suited to those conditions.

How can I confirm the gauge glass is seated correctly after installation?

Check that the 5/8 in diameter glass spans the full 12 in visible length between the two guard rods and that the needle-drain valve operates smoothly without leakage.

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