Danfoss 020B1010 NRV 6s v2 Check Valve – 1/4" ODF Solder, Straightway, Kv 0.67, 49 bar

Danfoss 020B1010 (type NRV 6s v2) is a straightway check valve that allows flow in the refrigeration line to pass in one direction only. It has a 1/4" ODF solder connection. Former order code: 020-1010.

Closes Reverse Flow — Prevents Refrigerant Migration to the Compressor During Standstill

When the compressor stops, the high-pressure gas on the discharge side tries to flow back. This backflow can both reverse the compressor and cause refrigerant migration to the crankcase — which means liquid slugging at start-up. The check valve closes this path.

In systems with parallel compressors, it prevents gas from the running compressor from escaping into the discharge line of the stopped compressor. In heat pumps and multi-evaporator circuits, it fixes the flow direction.

Technical Specifications (Official Danfoss NRV/NRVH Data Sheet)

• Danfoss code: 020B1010 (former code 020-1010) | Type: NRV 6s v2
• Connection: 1/4" ODF solder · straightway
• Kv value: 0.67 m³/h (Cv 0.77 gal/min)
• Min. opening differential pressure (OPD): 0.04 bar (0.58 psi)
• Max. working pressure (PS/MWP): 49 bar (710 psig)
• Oil compatibility: POE · PAG · PVE · PAO

The v2 Generation Is Better Than the Previous One

A higher Kv means less pressure loss, and a lower opening pressure means it can open even at low load — this makes a difference particularly in inverter systems and systems operating at partial load.

• ⚠️ 49 bar, not 46 bar. In the Danfoss table, the flare NRV 6-19 series is 46 bar, while the solder NRV 6s-19s series is 49 bar. This product is the solder version.
• Compatible refrigerants: R134a · R22/R407C · R290 · R32 · R404A/R507 · R407A/F/H · R410A · R448A/R449A/R449B · R450A · R452A/R452B · R454A/B/C · R455A · R513A · R515B · R516A · R600/600a · R1233zd(E) · R1234ze(E) · R1234yf · R1270
• ⚠️ Flow direction is essential: the arrow on the body indicates the flow direction. A check valve installed backwards closes the line completely.
• Mounting position: the straightway body can be mounted horizontally and vertically. In vertical mounting, flow must be upward.
• 🔧 Brazing warning: wrap the body with a wet cloth; excessive heat damages the spring and the sealing surface.
• NRVH difference: the NRVH version has a stronger spring (opening Δp 0.20 bar) and guarantees closing in vertical upward flow. In a horizontal line, the NRV is sufficient.