Hot Water Boiler Manual – Models H 635, H 650
6
Caution
The moisture condensation formed when igniting the boiler for the first time may be of such degree that the
boiler could be considered leaking erroneously. This condensation will disappear as soon as the boiler
temperature reaches 70 °C.
Adjust the secondary air volume so that no smoke appears at the top of the chimney after the fuel kindles
properly. The secondary air volume, however, needs to be adjusted keeping the boiler output into consideration.
Excessive secondary air causes supercooling in the heating chamber.
When refueling open the charging door carefully to avoid burning injury, should the flame blast abruptly.
Take care that the fuel level does not fall under the bottom edge of the underburning partition during operation.
Should this happen, it is necessary to add wood before coal to avoid fire extinguishing. Due to this, the boiler
shall be refueled in a timely manner and charging shaft shall be kept full at all times. This will reduce choking of
the boiler and increase the operating economy.
Ash and cinder shall be removed from the grate as needed during operation. This is performed using the grate
lever located on the side wall of the boiler. Short motions will make a small ash fall through, while long swings
towards the front side of the boiler will remove also bigger cinder pieces. The lever shall always be returned to
neutral position after the grate cleaning is completed. Check whether the ashtray compartment is filled with ash
completely, since this would obstruct supply of a sufficient air volume under the fire bars. If this check is not
performed properly, the fire bars and grate mechanism may overheat and be damaged.
Cleaning the boiler
The boiler shall be cleaned every 14 days based on the heating method. Cleaning of the heat-exchanging
surfaces is very important to maintain economical operation. Cleaning of this boiler is very easy, since the main
heat-exchanging surface is accessible after opening the cleaning door. Segments shall be cleaned using the
wire brush and persistent layer using scraper. Impurities fall through the rear section of segments onto the fire
bridge. From there they move through the burning shaft into the ashtray compartment. This shaft can be cleaned
through opening in the front wall, however, cleaning is required several times a season only. The secondary air
supply pipe shall be cleaned occasionally after removing the lid of the secondary air on the side of the boiler in its
bottom section. Cleaning shall be carried out using the steel brush designed for cleaning the segments. Clean
the flue gas side also. Impurities will fall into the ashtray compartment when the secondary air supply is open
fully. We recommend to knock on the side walls of the ashtray compartment in the place of the secondary air
inlet with tools in order to release dust settled on the walls of segments.
The boiler shall be cleaned thoroughly after the heating season and overall check shall be performed. This will
extend its service life. Cleaning of boiler, and the heat-exchanging surfaces in particular, is very important for the
operating economy. If the boiler is not cleaned properly the temperature of flue gases leaving to the chimney can
increase by up to 100 °C, which represents a substantial energy loss. After each cleaning check removal of soot
from the fire bridge under the segments (see Fig. 3, pos. 23).
ATTENTION !!!
Ash shall be put into incombustible container fitted with a cover.
G) Maintaining the boiler and heating equipment
Prior to commissioning the heating unit it is necessary to prime the water system. Soft water should be used, if
possible. The water shall be primed by the filling and discharging valve, which is located next to the return water
coupling.
The water shall not be taken from the boiler and heating equipment during operation. Check the water level in
the heating equipment occasionally. Refill if needed. To protect the equipment against rust, avoid discharging
water from the heating equipment or use anticorrosive agent for example INHIKOR, FRITERM
(www.velvana.cz); follow manufacturer's instructions.
Never allow the boiler to
exceed
90 °C. Fine bubbling when the exiting water exceeds 80 °C does not indicate a
defect. However, bubbling at lower temperatures is not allowable. This indicates incorrect assembly of the
heating system.
