IMI Hydronic MDF0 Instrucciones página 3

English
General
The measuring orifice MDF0 are classified within the Pressure Equipment Directive (European Parliament and
Council directive 97/23/EC) with the consistency level as set out in the table 1. (Maximum permitted pressure PS
= PN).
The measuring orifices are not CE-marked. Measuring orifices in category I-III will be covered by the CE-
marking of the installation in which they are included.
The measuring orifice are intended for heating and cooling systems, and tap water systems. (Fluids in group 2
according to the directive).
Differential pressure measurement should take place with extreme care especially if this concerns hot media.
Marking
The valve housing is marked with the following data:
TA: Manufacturer
DN and Max permitted temperature PS (PN) according to tabel 2
Charge No: Identification No
Flow arrow for the recommended direction of flow
BS 7350: Valid for DN 20-150, PN 16 only.
In addition to that stated on the valve housing, it applies:
• Max. permitted temperature: 120°C
• Min. permitted temperature: -10°C
Installation
The measuring orifice should be kept in a dry, clean location and protected from damage and contamination.
Before you install the measuring orifice, check that:
• the measuring orifice is clean and undamaged.
• the surfaces that are to seal against are clean and undamaged.
• there is enough straight pipe lengths before and after the measuring orifice.
10 D 5 D
The measuring orifice should be installed betweeen two counter flanges. Check that these counter flanges are
parallel and that the gaskets are according to given standard for flanges. Check also that the measuring orifice
and the gaskets are correctly centred before tightening.
Pressure switch and thermostat
In order to guarantee the lowest and highest pressure as well as to ensure that the temperature is not exceeded
the system should be fitted with a pressure switch and thermostat.
Commissioning
Test the pressure on the valve using cold water.
Tighten the flange joints and check for leakage in connection with commissioning.
Maintenance
The measuring orifice MDF0 are maintenance free under the condition that they are used within their normal
application area.
3