Danfoss 034L1075 KVP 22 Evaporator Pressure Regulator, 22 mm

KVP 22: an evaporator pressure regulator with 22 mm solder connections

The 034L1075 is a Danfoss KVP 22 evaporator pressure regulator with 22 mm (7/8 in) ODF solder connections. It keeps the pressure in the evaporator, and with it the evaporating temperature, from falling below the set value, which prevents icing of an air cooler or freezing of a water chiller. The adjustment range is 0 to 5.5 bar (0 to 80 psig) and the factory setting is 2 bar (29 psig).

The Kv value is 2.5 m3/h at the maximum proportional band of 1.7 bar. The maximum working pressure is 18 bar (260 psig), the test pressure is 19.8 bar and the medium temperature range is -45 to 130 C. A Schrader access port is provided and the body is marked with an engraved flow arrow.

Technical specifications

Evaporator pressure control in practice

KVP regulators are used when several evaporators work at different temperatures on one suction line: the one with the highest evaporating temperature gets a KVP so that it is held at a safe level. They are also used on chillers to stop freezing, in cooling of products like dairy and fresh produce, and in applications that need a constant evaporator temperature.

Rated capacities on the page at the proportional band are 3.6 kW on R404A/R507A, 2.8 kW on R134a, 4 kW on R22 and 3.7 kW on R407C. R1234ze(E) and R513A are listed for oil-free applications. UL, EAC and UA approvals are shown.

Setting and ordering

The regulator opens on rising inlet pressure, so it is installed in the suction line after the evaporator. Adjust it with the spindle under the cap while watching a gauge on the Schrader connection. Braze with the body cooled, since the bellows and seat are heat-sensitive.

Confirm the refrigerant, the pressure range, the connection and the capacity at your pressure drop. The product page lists 034L0025 as an identical product. Spare parts for the KV valve family are available.

Other types and sizes from the same Danfoss family that appear in the Danfoss store listing include KVP 12 (034L0021), KVP 15 (034L0022), KVP 28 (034L0026), KVP 35 (034L0032). These are listed for orientation only; each has its own datasheet values, so check size, connection and version before ordering.

Related Danfoss products: Danfoss 027H2081 ICS3 25-10 Pilot-Operated Servo Valve, 25 mm, Danfoss 027H2308 ICSH 25 Dual-Position Servo Valve, 25 mm, Danfoss 034L0058 KVL 22 Crankcase Pressure Regulator, 22 mm, Danfoss 148H3402 ORV 40 Oil Temperature Regulating Valve, 40 mm and Danfoss 034N0084 CPCE 22 Hot Gas Bypass Capacity Regulator.

How the KVP 22 regulates inlet pressure

According to the Danfoss KVP data sheet, the regulator is mounted in the suction line after the evaporator. It opens on a rise in inlet pressure, that is, when the evaporator pressure exceeds the set value, and it regulates inlet pressure only. Pressure variations on the outlet side do not affect the degree of opening, because the valve has equalization bellows whose effective area corresponds to that of the valve seat. Regulation is modulating: by throttling in the suction line, the amount of refrigerant gas is matched to the evaporator load.

The KVP also has a damping device that protects it against the pressure pulsations that normally arise in a refrigeration system. Danfoss states that this helps ensure a long service life without impairing regulation accuracy. Other design points listed in the data sheet are stainless steel bellows, a hermetic brazed construction, a compact angle body that can be installed in any position, and a 1/4 in. Schrader valve for pressure testing.

Three typical uses of an evaporator pressure regulator

• Constant evaporating pressure: keeps a constant evaporating pressure and therefore a constant surface temperature on the evaporator, which matters for display cases and cold rooms with sensitive products.
• Freeze protection: the regulator closes when evaporator pressure falls below the set value, for example to protect a water chiller from freezing.
• Multi-evaporator systems: it allows different evaporating pressures in two or more evaporators served by one compressor.

The data sheet also states that KVP 12 to KVL 22 may be used in Ex category 3 (Zone 2).

Data needed to size a KVP valve

Danfoss lists the information required for correct selection: refrigerant, evaporator capacity Qe in kW, the required evaporating temperature, the minimum evaporating temperature, the liquid temperature ahead of the expansion valve, and the connection type and size. When system conditions differ from the table conditions, the evaporator capacity is converted with correction factors for liquid temperature and valve offset, and the acceptable pressure drop across the valve is also considered. If you send these values with your enquiry, we can check that the 22 mm KVP 22 is the right size before quoting.

Documents and quotation

The reference document for this code is the Danfoss Evaporator pressure regulator, KVP AI555532694073en-000101 (manufacturer, unaltered), attached as the unaltered manufacturer PDF. See also regulators. Request a price for 034L1075 by sending the quantity; Seven Star LLC is an independent supplier in Muscat.