Lennox FLEXY II Series

IOM – FLEXY II – 1007 – E Page 29
ECONOMISER
Free cooling can be provided through the use of fresh air which is more appropriate
than excessiv e cooling amounts of return air.
The econom iser is f ac t ory fitt ed and tested prior to shipment.
It includes two dampers operating f rom a 24V actuator
RAIN HOOD
It also includes a factory f itted rain hood. Hoods is f olded during transportation to limit
risks of damage and must be unf olded on site as shown on fig. 9
EXTR ACTION
Installed with economiser assembly, the gravity exhaust dampers reliev e the pressure
when out s ide air is introduced int o t he sy s t em .
When large amount of f resh air is introduced into the system power exhaust fans can be used to equalise the pressures.
The extract ion f an runs when ret urn air dam pers are being clos ed and s upply air blower is in operat ion. The extrac t ion f an runs
when out door air dam pers are at leas t 50% open (adjust able v alue). It is overload prot ected.
NOTE: When horizontal flow configuration is required, the multidirectional roof curb will be installed.
0-25% FRESH AIR MANUAL
It is enough to loosen the mobile grid's screws and to make it slip.
0%: screw into limit stop on the right
25%: screw into limit stop on the left
F
LEXY II PRINCIPLE SKETCH
M
ULTIDIRECTIONAL ROOFCURB
PRINCIPLE SKETCH
E
NERGY RECOVERY MODULE PRINCIPLE SKETCH
R
ETURN ROOFCURB PRINCIPLE SKETCH
F
RESH
A
IR
R
ET URN
A
IR
E
XHAUST
A
IR
S
UPPLY
A
IR
ECONOMISER AND EXTRACTION
Fig. 9