Central ventilation with heat recovery unit KWL 250 - HELIOS ...

Central ventilation with heat recovery unit KWL 250
Operation and installation instructions no. 91581
INSTALLATION OF CONTROL CABLE
The control cable should be shielded and not be placed parallel to the mains supply
cable as interference may cccur.
OPERATION – ADJUSTMENT
The KWL 250 is to be controlled manually via the operation switch, which should
be mounted on a convenient place in the house. The operation switch allows following
functions:
– right press button (fan symbol): the desired step for the air flow volume can be
adjusted, the according light shows the chosen step:
MIN (speed step 1) basic air flow, for less intake air needs
NORMAL (speed step 2) normal air flow
MAX (speed step 3) full R.P.M., for maximum intake air needs
– left press button (+ symbol) only important in combination with electric heater
battery: The electric heater battery can be switched on and off. When switched
on, the heater battery starts heating when the temperature is lower than the temperature
pre set point (adjusted on the pot.)
red light (!)
blinking slow Filter needs to be changed ! (if filter monitor is installed)
blinking fast The temperature monitor (Pic .3, No.2.2) for the heater
battery tripped.
blinking constant Both messages appeared..
green light (+) blinking, when availability of heater element is switched
on,
yellow light (°C) Blinking, when electric heater battery is in use.
Speed step 2 can be adjusted to the size of the dewelling. Open the unit is to be
opened. Then change the two connections, marked with speed step 2 at the
transformer according to wiring diagram in the unit. Isolate from the mains supply
before comencing this work all mains.
Note: If the electrical supply of the KWL 250 is disconnected, the unit will restart
automatically with basic air flow (speed step 1) and the availability of the heater
battery.
N.B.: For good room climate and to avoid damage from condensation, the KWL
250 should never be switched off apart from cleaning/maintenance work or possible
faults.
Settings on DIP-switch
Switch- Standard- Function
No. setting
1 ON ON position: Electric heater battery to be switched off
during frost protection modus. (must not be OFF!)
2 OFF ON position: Electric heater battery to be switched off on
speed step 1.
3 OFF (only with timer) On position:
Supply air to be lowered by 3 °C at night.
(only if a heater battery is used)
4 OFF (only with timer) ON position:
Air flow volume to be lowered on speed step 1 at night
5 OFF –
6 ON –
Setting the electric heater battery (KWL 250 EH)
The pot for temperature preselection fot the heater battery (pic.3, No.1) is placed
on the extract air cover plate. This pot is factory set at 20 °C and can be adjusted
as required for the supply air. Do not set higher than 25 °C. The heating battery is
protected against overheating via a self resetting temperature cut out (pic. 3, No.
2.1). This temperature cutout switches off automatically when the temperature of
65°C has been reached. It switches back on automatically whenf the heater battery
has cooled down. As an additional safety control, a second, non self resetting
thermostat (temperature cut out), switches off the whole unit automatically if a
temperature of 80°C is exceeded. This thermostat can be manually reset by pressing
the reset button, which is accessible by removing the white plastic lid.
Regulating the water heater battery (KWL 250 WW) (Picture 2)
The progressive heating is via the built-in water heater battery (18). The supply
and return pipeing on site must be so routed or fully insulated supply to prevent
frost damage. A thermostatic valve with remote sensor is to be fixed in the supply
pipe of the heater battery on site. The remote controller is to be fixed above the
KWL-connecting spigot “supply air“ into the supply air ducting. Usung the remote
sensor and the thermostatic valve in the water supply the supply air temperature
is controlled. The thermostatic valve is not included and must be supplied and set
on site.
A water control system which is a Helios accessory (ref. WHST 300) is shown in
picture 2. This provides a complete control for the water supply and return.
ATTENTION: If the supply air ducting is to pass through cold areas Insulation must
be applied to prevent temperature losses on before entering the room being supplied.
Frost protection of the water heater battery (Picture 2)
Intake and extract ductwork must be insulated to avoid ice build up on the water
heater battery. Immediately after the water heater battery there is a frost protection
thermostat (20). If the temperature off the water heater battery is lower than to +5
°C the thermo sensor closes. This volt free contact of the thermostat is to be
connected with the heater control so that the shunt valve opens as soon as the
heater and circulating pump are switched off. This forced control avoids the ice
build up on the water heater battery. If the unit is switched off at any time in winter
the warn water coil should be drained off to prevent frost damage to the coil.
Frost protection of the heat exchanger battery:
The sensor (Picture 3, No. 3) for frost protection is located in the extract air ducting.
This sensor controls the supply air fan so that ice and frost can not build up in
the extract air ducting or the heat exchanger. Warm air e.g. from the bathroom
etc. contains high humidity that can condensate easily. Therefore the temperature
in the heat exchanger must not drop so low that water freezes in it. When the outside
temperature drops the extract temperature drops as well. If the temperature of
the extract air is close to the freezing point, the supply air fan switches off for a
certain period of time until the heat exchanger is warms up sufficienty. The frost
protection thermostat is factory set and normally needs no adjustment.
– Summer Service
During the warmer months (apart from the heating period) it is not necessary to recover
heat. The recovery battery can be replaced with a summer insert (Accessory KWL-
SOE 250, Ref. No. 0855). Through this the outside air enters directly into the house
without being warmed up. The temperature adjusting pot (KWL 250 EH) or the thermostat
(KWL 250 WW) must be positioned on low temperature otherwise unnecessary
heating will be the result. Remember to reset the thermostat the following autumn
and replace the heat exchanger unit again.
– Accessories, switches, controllers
It is not admissible to use accessories which are not recommended by Helios, in
case of damage this will lead to a loss of warranty. The use of an electronic or
transformer speed controller is not permissible.
CLEANING AND MAINTENANCE
Isolate the unit from the electric supply before carring out any work on the unit.
– Opening of door (Pic. 3, page 4)
The door is secured with screws and can be opened after removing the screws.
– Filter
The unit filters are as follows:
• Outside air: Prefilter G 3 Part.-No. 0043
Finefilter F 5 Part.-No. 0044
alternatively: (F 7, Part.-No. 0045, eg for persons with allergies)
• Extract air: Prefilter G 3 Part.-No. 0043
The outside air and the extract air filter are to be checked and changed regularly,
depending on degree of pollution at least every 3 months. For hygiene reasons,
the fine filter should be changed after every year at least. Check the correct the air
flow direction when refitting the filter. In areas of heavy air pollution, a filter box
(LFBR 125, Part.-No. 8577) should to be placed in an easily accessible area upstream
of the unit. These filters must be regullary cleaned and changed.