Maintenance - Komfovent DOMEKT Series Installation And Service Manual

5. MAINTENANCE

It is recommended to carry out routine maintenance of the air handling unit 3–4 times per year. With
units mounted on ceilin do not release the door to the key to open the door. Do not release the door to
swing freely, but open it slowly at a 90 degree angle. Be careful while opening, because clogged filters
might fall out.
Besides preventive maintenance inspection, the following operations should be performed:
1. Rotary heat exchanger check. Inspection of the rotary heat exchanger is performed once per year. Free
rotation of the rotary heat exchanger, continuity of the rotating belt, absence of damages of the rotor
drums and the seal gasket are checked. It is necessary to check the stretch of belt. Free belt will slide and the
efficiency of rotary heat exchanger will fall down. To reach maximal efficiency, rotor must turn at
least 8 times per minute. Polluted heat exchanger will decrease efficiency. Clean heat exchanger
with an air blast or wash with tepid water. Check out water falling on the electric motor.
2. Plate heat exchanger check. Inspection and dedusting of the plate heat exchanger is performed once
per year (it is removed from the unit and blown with an air blast or washed with tepid water).
Plate heat exchanger cleaning. If plate heat exchanger cleaning by compressed air is not effective,
it can be washed with soapsuds, or if needed – use degreasing soak for metal (aluminum) cleaning.
Leave plate heat exchanger to dry in a warm place. It can be mounted only when it is absolutely dry.
Note: plate heat exchanger may be replaced with summer cassette (for units without by pass), when re-
cuperation is needless.
3. Fans check (once per year). Polluted fans decrease efficiency.
Before performing any inspection work, check whether the unit is switched off
from the electric power supply.
Fans should be carefully cleaned with textile or soft brush. Do not use water. Do not break balance.
Check if direction of fan turns is right, because wrong direction of turns gives only 30 % rating. Check
if fan freely rotates and is not mechanically damaged, if impeller does not touch suction nozzles, fan
does not spread noise, the pressure tubes are connected to the nozzle (if it is required), mounting
bolts are screwed.
The rubber couplings connecting the motor base and the unit should be visually inspected for signs
of wear and replaced as necessary.
Any unusual noise or vibration when the fan is running should be immediately investigated, as this
usually an indication of wear or imbalance in the fan system.
4. Air heater check. Recommended to perform periodical inspection and cleaning of heater. Check
the plates of water air heater. The air heater is cleaned with hoover from supply air side or with air
blast from exhaust air side. If it is very dirty, wash with tepid water, which will not make corrosion of
aluminium. Check if position of return water temperature sensor is right. Check if electric air heater
is properly fixed, wires connections are not damaged and heating elements are not bent. They can
be damaged or bent due to uneven heat or uneven and turbulent air direction. Check if electric air
heater is clear of unnecessary things and heating elements are not clogged, because this can cause
unpleasant smell or in the worst case – dust can start burning. Air flow through the air heater should
be greater than 1,5 m/s. Heating elements can be cleaned with hoover or wet textile.
5. Air damper check (if it is required). Not fully opened outside air damper rises up the pressure in
the system. Water air heater can freeze if outside air damper does not fully close in not working air
handling unit. Mounting and running of air damper should be checked and regulated.
6. Air filter clogging check. Change air filters when air filter clogging is indicated. We recommend
changing filters at least twice per year: before and after heating season or more
Filters are one time used. We do not recommend cleaning them. Stop the air handling unit before
changing filters.
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Clogged filters unbalance ventilation system, air handling unit uses more power.
UAB KOMFOVENT we reserve the right to make changes without prior notice
D_21-03
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