7/27/2019 Technical Leaflet Cim 788

1/7

Pagina 1 di 7

Technical leaflet Cim 788 ENRevisione 0

Emissione 01/2011

TECHNICAL INFORMATION

Pre-setting manual balancing valves

CIM 788

Description

Cim 788 balancing valves are suitable for

both heating (LPWH) and cooling

applications, ensuring high accuracy flow

balancing across all valve settings.

tutto il campo di regolazione della valvola.

Cim 788 pre-setting balancing valve is

made of ADZ brass material with female-

female threads according to ISO 7 and it is

suitable for both heating and coolingapplications at working pressures up to 25

bar, within the temperature range of -

10C and +120C.

The main features ofCIM 788pre-setting balancing valve are as follows:

Screw driver adjustable pre-setting.

11 positions flow pre-setting.

Plastic cap enabling the valve to be closed and opened at pre-set Kv value.

An EPDM lined valve plug providing tight shut-off for isolation purposes..

Designed to be upgraded with thermoelectric actuator (Cim 788NC, Cim 788NO, Cim 788NC24, Cim

788NO24, Cim 788PRO).

Fig 1

7/27/2019 Technical Leaflet Cim 788

2/7

Pagina 2 di 7

Technical leaflet Cim 788 ENRevisione 0

Emissione 01/2011

Installation procedure

Before installation ofCIM 788, check that inside the valve and the pipes there are no foreign matters which

might damage the tightness of the valve.

When installing the valve, please make sure to have a pipe length 5 times the DN upstream the valve and 2

times the DN downstream, and pay attention to the arrow direction casted on the valve body, which shall be

the same as the flow one. The valve can be installed in any position if fluid is clean; if this is not the case,

avoid upside down installation.

Burr pipe connections after having threaded them and distribute the sealing material on pipe threads only

and not on valve threads. The sealing material quantity shall be according to the dimension of parts to be

coupled. An excessive quantity of sealing material could submit the threaded ends to extreme stress and/or

fall inside the valve and cause problem to the flow.

For assembly purposes, use a spanner, not a pipe wrench, by applying necessary working torque only on

the valve end nearest the pipe. This helps get a firmer grip and avoids potential damages to valve body.

Make sure that pipe threading length is not longer than valve threads.

Regulating

Remove the blue plastic cap of the upper part of the bonnet to pre-set the flow rate. Looking at the data

shown in the herewith attached diagrams, regulate the flow by rotating the hexagonal stem-ring with a

screwdriver inserted in the relevant slot. When regulating is carried out, the slot position will show the

opening grade of the obturator. The index scale shows 11 values going from the minimum flow rate (0) tothe maximum one (10). The reading of this flow rate can be done by using the differential manometer Cim

726. This interfaces with the balancing valve through two sensors placed at the ends of the valve. To protect

the bonnet, replace the cap and leave it unloosed to enable the water flow. On the other hand, if the

interception of the fluid is required, tight the cap firmly and completely.

Fig 2

7/27/2019 Technical Leaflet Cim 788

3/7

Pagina 3 di 7

Technical leaflet Cim 788 ENRevisione 0

Emissione 01/2011

Fig 3

Maintenance

As a rule, the balancing valve does not need any maintenance. In case of replacement or need of

disassembling of some components of the valve,

make sure that the installation is not under service

or pressure.

Should you need to replace the tightening OR (13)

between body (1) and bonnet (2), follow the

instructions given here below:

Remove the blue cap (19);

Take note of the pre-setting position on a

sheet of paper;

Unscrew the bonnet (2) with a key, acting onthe hexagonal side;

Replace the Oring (19);

Screw the bonnet (2) again until the

complete tightening on the valve body (1),

acting on the hexagonal side;

Make sure that the index scale (14) has not been rotated during bonnet removal. To this purpose,

rotate clockwise the hexagonal stem-ring (4) with a screwdriver until the stop. In this position the slot

of the stem-ring shall be aligned with the 0 value of the index scale (14). If not, remove the index

scale (14) with the screwdriver and replace it aligned as described above.

Place the stem-ring (4) as made during the previous regulation;

Replace the blue cap (19) and leave it unloosed to enable the water flow.

The following table shows the dimensions of the full range of valve CIM 788. The data D means the length

of the body threads.

DN A B C D F

106 58 77 16 35

107 60 80 19 35

1 107 62 87 21 35

Fig 4

7/27/2019 Technical Leaflet Cim 788

4/7

Pagina 4 di 7

Technical leaflet Cim 788 ENRevisione 0

Emissione 01/2011

Spare parts

Cim 788 pre-setting balancing valve are designed to be upgraded with different type of thermoelectric

actuators to open and close the valve on heating circuit distributors on floor heating systems. The actuator is

able to keep the valve closed until a maximum differential pressure of 2,2 bar. The following versions are

available:

Cim 788NC normally closed 230V-50/60Hz(actuator only Cim EMV 310/NC230)

Cim 788NO normally open 230V-50/60Hz(actuator only Cim EMV 310/NO230)

Cim 788NC24 normally closed 24V-50/60Hz(actuator only Cim EMV 310/NC24)

Cim 788NO24 normally open 24V-50/60Hz(actuator only Cim EMV 310/NO24)

The thermoelectric actuator assembling on the valve is made with a

plastic adaptor, screwed on the bonnet, that enables the actuatorassembling by snap-on device. The technical features of these

thermoelectric actuators are the following:

Operating power: 1,8 WDegree/Class of protection: IP54/II (in all installationpositions)Actuator stroke: 4,5 mmActuating force: 100 N 5%Connecting cable: 2x0,75 mm

2PVC grey

Cable length: 1000 mmConnection: valve adapter VA80 (NC)

Valve adapter VA50 (NO)

Cim 788PRO (actuator only Cim EMV 310/PRO24) is the version with thermoelectric actuator normally

closed with internal electronic unit for proportional control of valves used in building management systems.

The technical features of proportional thermoelectric actuators are the following:

Operating voltage: 24 V, -10% fino a +20%, 50/60HzControl vol tage: 0-10 V DCInput resistance: 100 kOhmOperating power: 1,8 WDegree of p rotection: IP54Actuator stroke: 4,5 mmActuating force: 100 N 5%Activation current max:

7/27/2019 Technical Leaflet Cim 788

5/7

Pagina 5 di 7

Technical leaflet Cim 788 ENRevisione 0

Emissione 01/2011

Diagrams and tables

CIM 788 1/2 DN 15

Kvs value registered on the binder points placed at the ends of the valve

Kvs (flow rate in m3/h @ 1bar pressure drop)

Pre-setting position

0 1 2 3 4 5 6 7 8 9 10

0,26 0,32 0,46 0,70 0,97 1,23 1,44 1,58 1,65 1,68 1,70

7/27/2019 Technical Leaflet Cim 788

6/7

Pagina 6 di 7

Technical leaflet Cim 788 ENRevisione 0

Emissione 01/2011

CIM 788 3/4 DN 20

Kvs value registered on the binder points placed at the ends of the valve

Kvs (flow rate in m3/h @ 1bar pressure drop)

Pre-setting position

0 1 2 3 4 5 6 7 8 9 10

0,26 0,32 0,46 0,70 1,01 1,42 1,80 2,17 2,48 2,71 2,90

7/27/2019 Technical Leaflet Cim 788

7/7

Pagina 7 di 7

Technical leaflet Cim 788 ENRevisione 0

Emissione 01/2011

CIM 788 1 DN 25

Kvs value registered on the binder points placed at the ends of the valve

Kvs (flow rate in m3/h @ 1bar pressure drop)

Pre-setting position

0 1 2 3 4 5 6 7 8 9 10

0,26 0,35 0,50 0,73 1,06 1,51 1,94 2,39 2,82 3,13 3,50