MHS Boilers Alpha Jetstream MD, Инструкция по установке и эксплуатации

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Water side The fully watercooled sections are joined by cast iron conical nipples, and distribution
of boiler pipe fitted to the return ensures even the temperature distribution throughout the boiler.
The cast iron sections are to BS.1452 Grade 200 with 7 mm wall thickness. Return and
flow connections to heating system are provided by stub-pipes at the rear of the boiler.
Under no circumstances should the boiler be fired when its circulation volume is less than
a recommended minimum volume calculated according to the following formula:
The following table provides hydraulic resistances at various water volumes relativ to boiler
Dt flow/return. The difference between flow and return temperatures of the bolier should
not be greater than 20 C to provide convenient operating conditions in the boiler:
Boilers must be connected to a chimney by using the shortest possible connector which
should be insulated by mineral wool or similar material. The flue connector must rise at
Flue design an angle from boiler to chimney of not less than 10º. Conditions creating high resistance
and chimney to gas flow should be avoided in the flue connector. The flue outlet of the boiler should
installation not support the weight of chimney.
The draft generated by the chimney should be capable of overcoming the chimney
resistance.
Chimney calculations should be carried out in compliance with the standards. Conditions
of existing chimney should be checked and proper precautions should be taken against
excessive cooling and condensation. Chimneys should be lined if necessary
Positive draught conditions must be avoided
Negative draught conditions should be contained within -3 mm wg. (30Pa) for optimum
boiler performance.
The following table shows typical flue gas volumes at gross flue temperature of 190°C and
ambient air temperature of 20°C.
146.9 528.9 MD9 300 139.9 503.8
109.2 393.1
MD8 262 122.2 439.9 128.3 461.9
MD7 223 104 374.5
70.5 253.9
MD6 181 85.8 309 90.1 324.4
MD5 144 67.2 241.8
51.4 185.1
kW g/sec kg/h g/sec
MD4 105 49 176.3
TECHNICAL INFORMATION
Boiler type Output
Flue gas volume
Light Oil
C02=13%
Natural gas G20
C02=9.5%
kg/h
l/s
252
Output kW
=
∆ t=10
o
C ∆ t=15
o
C ∆ t=20
o
C
Type
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l/s l/s kPa l/s kPa l/s kPa
MD 4 0.41 2.5 8.1 1.66 3.7 1.25 2.2
MD 5 0.58 3.42 16.0 2.28 7.2 1.71 4.1
MD 6 0.75 4.38 15.5 2.92 6.8 2.19 3.9
MD 7 0.88 5.33 20.6 3.53 9.2 2.65 5.2
MD 8 1.05 6.23 29.5 4.15 13.2 3.13 7.5
MD 9 1.19 7.14 39.0 4.76 17.4 3.57 9.8