A) Basic Features Of This Boiler Line; B) Technical Description - Opop H 635 Manual

The design of H 635 and H 650 hot water boilers makes them suitable for the central heating of family houses
and small buildings, such as service providers' facilities, kindergartens, and so on. These boilers feature two
chambers, which allow combustion of lignite.

A) Basic features of this boiler line

a) The large-volume charging shaft which allows maximization of time between individual fuel additions.
It also ensures a long-term operation without frequent interventions of operators.
b) The large refueling hole allowing an easy refueling.
c) An easy change of the combustion method. Two combustion methods are available: the underburning
method and the burn-through method. This feature allows selecting the combustion technology based on the
fuel used (see Fig. 6 & 7).
d) The secondary air supply and its control independent of the primary air ensure virtually smoke-free
combustion with the minimum air pollution level and a perfect fuel combustion. Combined with the automatic
combustion air supply controller, the unit ensures economical and uniform keeping of the heating water
temperature selected.
e) An easy cleaning of the boiler allows keeping its permanent maximum efficiency. The cleaning may be
carried out during operation after opening the cleaning door which provides an access to the primary heat
exchanging surfaces. All burning residues fall into the ash tray during cleaning. There is no need to remove
them elsewhere.
f) The system of continuously ascending flues prevents the low-temperature condensation and thus corrosion
of the boiler body in its bottom section. This system reduces the demand of the boiler with respect to the
chimney effect considerably.
g) The large-volume ashtray compartment allows a long-term operation with no need of the frequent ash
removal.

B) Technical description

The boiler the height of which is 1,606 mm, forms a rectangle when looking from above in the direction from the
front face towards the rear section (see Fig. 3 & 4).
Both height and depth (730 mm) of both output models are identical. The width varies based on the type and
output of the boiler and it ranges from 390 mm up to 520 mm.
The boiler body is welded of the steel plates. Thickness of the internal walls coming into contact with the fuel is 4
mm, while thickness of the external shell is 3 mm. In addition to this, the boiler body is fitted with the cover plates
with the thermal insulation layer placed underneath. When looking at the front, the boiler body is fitted with
ashtray, refueling and cleaning doors.
There is a large refueling shaft behind the charging door which is terminated by the sliding grate in the bottom
section. The opposite wall of the shaft is a water-cooled underburning partition. This partition is fitted with the
tilting flap which allows selection between underburning or through-burning of the fuel. Behind the underburning
partition there is a burning chamber. In the bottom section of this chamber there is a narrowed diffuser section
into which the secondary air is supplied via two water-cooled pipes.
In the top section of this chamber there is a water-cooled fire bridge. The flue gases flow around the fire bridge
onto the main heat-exchanging surface which consists of the vertically arranged segments. The flue gases are
fed into the smoke neck through a return flue. This return flue through segments may be disabled by the closing
flap which is controlled by a lever on the top side section of the boiler. The heat-exchanging segment surface is
accessible for cleaning after opening the cleaning door.
Hot Water Boiler Manual – Models H 635, H 650
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