Unigas RX1025.1 Manual Download

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PART I: SPECIFICATIONS

How to read the burner “Performance curve”

To check if the burner is suitable for the boiler to which it must be install-
led, the following parameters are needed:



furnace input, in kW or kcal/h (kW = kcal/h/860);



backpressure (data are available on the boiler ID plate or in the
user’s manual).

Example:
Furnace input: 600kW
Backpressure: 4 mbar
In the “Performance curve” diagram, draw a vertical line matching the fur-
nace input value and an horizontal line matching the backpressure value.
The burner is suitable if the intersection point A is inside the performance
curve.
Data are referred to standard conditions: atmospheric pressure at 1013
mbar, ambient temperature at 15° C.

Checking the proper gas train size

To check the proper gas train size, it is necessary to the available gas pres-
sure value upstream the burner’s gas valve. Then subtract the backpressure.
The result is called

pgas.

Draw a vertical line matching the furnace input

value (600kW, in the example), quoted on the x-axis, as far as intercepitng
the network pressure curve, according to the installed gas train (DN65, in the
example). From the interception point, draw an horizontal line as far as
matching, on the y-axis, the value of pressure necessary to get the reque-
sted furnace input. This value must be lower or equal to the

pgas

value, cal-

culated before.

Campo di lavoro bruciatori

Tipo P60 Mod. M-xx.x.IT.A.0.50 - M-.xx.x.IT.A.0.65

-1

100

200

300

400

500

600

700

800

900

Potenza kW

Contropressione in camera di

combustione mbar

backpressure in

mbusti

on ch

amber

(mb

ar)

Power kW

100

200

300

400

500

600

700

800

900

Potenza / Output (kW)

Minima pressione gas in

rete / Minimum inlet gas

pressure (mbar)

Rp 2" (50)

DN65

Power kW

min

imum gas

essure in

k m

DN65

Combustion head gas pressure curves

Combustion head gas pressure depends on gas flow and combustion chamber backpressure. When backpressure is subtracted, i

depends only on gas flow, provided combustion is properly adjusted, flue gases residual O2 percentage complies with “Recommended

combustion values” table and CO in the standard limits). During this stage, the combustion head, the gas butterfly valve and the

actuator are at the maximum opening. Refer to , showing the correct way to measure the gas pressure, considering the values o

pressure in combustion chamber, surveyed by means of the pressure gauge or taken from the boiler’s Technical specifications.

Measuring gas pressure in the combustion head

In order to measure the pressure in the combustion head, insert the pressure gauge probes: one into the combustion chamber’s

pressure outlet to get the pressure in the combustion chamber and the other one into the butterfly valve’s pressure outlet of the burner.

On the basis of the measured differential pressure, it is possible to get the maximum flow rate: in the pressure - rate curves (showed on
the next paragraph), it is easy to find out the burner’s output in Stm

/h (quoted on the x axis) from the pressure measured in the

combustion head (quoted on the y axis). The data obtained must be considered when adjusting the gas flow rate.

Note: the figure is indicative only.
Key
1 Generator
2 Pressure outlet on the combustion chamber
3 Gas pressure outlet on the butterfly valve
4 Differential pressure gauge

Fig. 4

ATTENTION: THE BURNED GAS RATE MUST BE

READ AT THE GAS FLOW METER. WHEN IT IS NOT

POSSIBLE, THE USER CAN REFERS TO THE

PRESSURE-RATE CURVES AS GENERAL

INFORMATION ONLY.