Danfoss KVP 12, KVP 15, KVP 22, KVP Data sheet

Data Sheet

Evaporator pressure regulator Type KVP

Maintains a constant evaporating pressure

The KVP is mounted in the suction line after the evaporator and is used to:

1.

Maintain a constant evaporating pressure and thereby a constant surface temperature on the evaporator. The regulation is modulating. By throttling in the suction line, the amount of refrigerant gas is matched to the evaporator load.

2.

Protect against an evaporating pressure that is too low (e.g. as protection against freezing in a water chiller). The regulator closes when the pressure in the evaporator falls below the set value.

3.

Dierentiate between the evaporating pressures in two or more evaporators in systems with one compressor.

Features

• Accurate, adjustable pressure regulation

• Wide capacity and operating range

• Pulsation damping design

• Stainless steel bellows

• Compact angle design for easy installation in any position

• “Hermetic” brazed construction

1

•

⁄4 in. Schrader valve for pressure testing

• Available with are and ODF solder connections

• KVP 12 – KVL 22: may be used in the following EX range: Category 3 (Zone 2)

AI249086497299en-001001

= 8 mm

1 2

3

4

5

6

10 11 12

13

7 8 9

12345678910111213

Protective cap

Gasket

Setting screw

Main spring

Valve body

Equalization bellows

Valve plate

Valve seat

Damping device

Pressure gauge connection

Cap

Gasket

Insert

Evaporator pressure regulator, type KVP

Functions

Figure 1: Design/Function for KVP

The evaporator pressure regulator, type KVP opens on a rise in pressure on the inlet side, i.e. when the pressure in the evaporator exceeds the set value.

Type KVP regulates inlet pressure only. Pressure variations on the outlet side of the regulator do not aect the degree of opening as the valve is equipped with equalization bellows (6).

The bellows have an eective area corresponding to that of the valve seat neutralising any aect to the setting.

The KVP is also equipped with a damping device (9) providing protection against pulsations which can normally arise in a refrigeration system.

The damping device helps to ensure long life for the regulator without impairing regulation accuracy.

Danfoss

34L181.10

C

S

B

O

P

CBSOP

Capacity

bar

Setting

oset

P- band

Evaporator pressure regulator, type KVP

Figure 2: P-band and Oset

Proportional band

The proportional band or P-band is dened as the amount of pressure required to move the valve plate from a closed to a fully open position

Example

If the valve is set to open at 4 bar and the valve P-band is 1.7, the valve will provide maximum capacity when the inlet pressure reaches 5.7 bar.

Oset

The oset is dened as the permissible pressure variation in evaporator pressure (temperature). It is calculated as the dierence between the required working pressure and the minimum allowable pressure.

The oset is always a part of the P-band.

Example with R22

A working temperature of 5 °C ~ 4.9 bar is required, and the temperature must not drop below 0.5 °C ~ 4.1 bar. The oset will then be 0.8 bar.

When selecting a valve, be sure to correct the evaporator capacity based on the required oset.

Features

Description

Refrigerants

R22, R134a, R290

(1)

, R404A, R407A, R407C, R407F, R407H, R448A, R449A, R449B,

R450A, R452A, R454A

(1)

, R454C

(1)

, R455A

(1)

, R507, R513A, R515B, R516A, R600

(1)

,

R600a

(1)

, R1234ze(E)

(1)

, R1234yf

(1)

, R1270

(1)

Regulating range 0 – 5.5 bar

Factory setting = 2 bar

Max. working pressure

PS/MWP PS = 18 bar

Max. test pressure

Pe = PS × 1.1 = 19.8 bar

Medium temperature range

-45 – 130 °C

Maximum P-band KVP 12 – 22: 1.7 bar

KVP 28 – 35: 2.8 bar

Kv-value

(2)

with oset 0.6 bar

KVP 12 – 22: 1.7 m3 / h

KVP 28 – 35: 2.8 m3 / h

Kv-value

(2)

with maximum P-band

KVP 12 – 22: 2.5 m3 / h

KVP 28 – 35: 8.0 m3 / h

Type

Pressure drop in regulator ∆p

Evaporating temperature t

e

[°C]

[bar]

-15

-10-505101520

KVP 12 KVP 15 KVP 22

0.122.3

2.6

2.9

3.2

3.644.4

0.2

2.8

3.1

3.644.555.5

6.1

0.3

3.2

3.7

4.2

4.8

5.466.7

7.4

0.4

3.6

4.1

4.8

5.4

6.1

6.8

7.6

8.4

0.5

3.8

4.4

5.1

5.9

6.7

7.5

8.4

9.3

0.6

3.9

4.7

5.5

6.3

7.1

8.1910

Evaporator pressure regulator, type KVP

Product specication

Technical data

Table 1: Technical data for KVP

(1)

KVP 12 – KVP 22 only

(2)

The Kv value is the ow of water in [m3 / h] at a pressure drop across valve of 1 bar, ρ = 1000 kg / m3.

This product (KVP 12 – KVP 22) is evaluated for R290, R454A, R454C, R455A, R600, R600a, R1234ze(E), R1234yf, R2170 by ignition source assessment in accordance with standard EN ISO80079-36. Flare connections are only approved for A1 and A2L refrigerants.

For complete list of approved refrigerants, visit store.danfoss.com and search for individual code numbers, where refrigerants are listed as part of technical data.

Sizing

For optimum performance, it is important to select a KVP valve according to system conditions and applications.

The following data must be used when sizing a KVP valve:

• Refrigerant

• Evaporator capacity: Qe in [kW]

• Evaporating temperature (required temperature): te in [°C]

• Minimum evaporating temperature: te in [°C]

• Liquid temperature ahead of expansion valve: tl in [°C]

• Connection type: are or solder

• Connection size in [in.]

Capacity tables

Table 2: Regulator capacity Qe 1) [kW] with oset = 0.6 bar, R134a