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Brass tee fitting with three threaded connections

Legend Valve

Legend Valve 800-246 Fill/Expansion Tee Accessory

SKU CH-XTNB-N6B0X

Fill/expansion tee connects expansion tank and fill valve with 1/2" MNPT threads for T-88 and HS-808 systems

  • Connects expansion tank and fill valve in one fitting
  • 1/2" MNPT threads match standard piping connections
  • Designed for T-88 and HS-808 system compatibility
  • New Legend Valve component ready for installation
  • California Proposition 65 warning applies to this product

Fill/Expansion Tee Connector

The Legend Valve 800-246 is a fill and expansion tank tee connector designed for hydronic heating systems. It provides a 1/2 inch MNPT connection point compatible with T-88 and HS-808 series components. This accessory is intended for installers and maintenance professionals managing boiler or radiator loops.

Thermal and Pressure Role

The tee integrates into the system piping to accommodate an expansion tank and fill valve assembly. It handles the pressures and temperatures standard to residential hydronic circuits without requiring external power. No moving parts or electrical draw are involved in its operation.

Compatibility and Safety Notes

The connector specifically fits T-88 and HS-808 equipment, so it is not suited for systems using different manifold or valve standards. California Proposition 65 warnings apply because the product contains chemicals identified as causing cancer and reproductive harm. Installers should observe appropriate handling precautions.

How it compares

Measured against everything we stock in Radiator Fans & Boiler Parts, at today’s prices. Recalculated every night.

Price $21.99
Cheaper than about 60% of the 95 comparable items (median $25.99).

Specifications

Product
Brand nameLEGEND VALVE

Questions about this item

How do I install the 800-246 tee onto the T-88 or HS-808 without cross-threading the 1/2" MNPT connection?

Thread the tee by hand onto the expansion tank or fill valve until the taper seats, then tighten one to two turns with a wrench; the male NPT thread seals on the taper, so over-tightening distorts the threads and causes leaks.

What maintenance will the 800-246 tee require after installation in a hydronic system?

Inspect the tee annually for corrosion or mineral build-up at the joint; if the brass body shows green deposits or the threads weep, replace the tee rather than re-sealing it.

What is the first limit the 800-246 tee reaches under sustained high-temperature cycling?

The brass body and NPT threads tolerate normal boiler temperatures, but repeated thermal expansion can fatigue the taper seal, making thread deformation the first failure mode.

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