Heated Rear Screen; Pollen Filter; Engine Bay Ventilation; Cooling Fans & Re-Circulation Pump - Lotus Evora Service Notes

Lotus Service Notes
- The interior fan will operate at full speed;
- All airflow will be directed to the windscreen;
- Air conditioning will be switched on (may be overridden by manual de-selection).
Note that an appropriate temperature setting must be selected manually.

Heated Rear Screen

Due to the heavy current demand, this switch will operate only when the engine is running. Under this
condition, the HRS and door mirror heating elements will be activated for a period of 10 minutes before auto-
matically switching off. The switch and heating cycle will default off next time the ignition is turned on.

Pollen Filter

Mounted at the air intake to the HVAC unit, is a folded paper element pollen filter which should be renewed
at intervals specified in the Maintenance Schedule. An access panel beneath the front body hatch is provided
to allow filter replacement by simply pulling out the old element and pressing in the new.

Engine Bay Ventilation

Various intake and outlet vents are provided in the rear body to allow ventilation and cooling of the engine
bay.
- Intake vents ahead of the rear wheelarches provide ambient air for the engine air intake, and for engine
bay cooling.
- Outlet grilles around the top of the tailgate panel exhaust hot air from around the catalytic converter at the
front of the engine bay.
- An outlet grille at the base of the tailgate glass, and to either side, exhaust hot air from around the catalytic
converter at the rear of the engine bay.
PN.3 - COOLING FANS & RE-CIRCULATION PUMP
The two cooling fans are fitted on the top side of the radiator/condenser package, and the coolant re-
circulation pump is mounted at the LH side of the engine bay, beneath the air cleaner. Both the fans and pump
are controlled by the engine management ECU using data provided by the engine coolant temperature sensor
and the a.c. trinary switch mounted in the refrigerant line between receiver-drier and evaporator.
Cooling Fans
The cooling fans are switched as a pair, and will operate at half speed (connected in series) when cool-
ant temperature reaches 98°C on rise (94°C with a.c. on), and switch off at 96°C on fall (92°C with a.c. on). If
coolant temperature rises to 105°C (96°C with a.c. on), the fans will switch to full speed (connected in parallel),
reverting to half speed on fall at 98°C (94°C with a.c. on).
Note that the temperatures displayed on the instrument panel may differ from the programmed values
described above due to instrument damping lag.
The fans are also activated by signals received from the trinary switch; the fans will run at low speed for
pressures between 13 - 18 bar, and at high speed for pressures over 18 bar.
Certain types of ECU detected engine fault will also cause the fans to be activated as an engine protection
measure. If the ECU receives a coolant temperature sensor signal voltage outside of the acceptable range, a
default setting equating to 60°C will be substituted, and the cooling fans will run at half speed.
Engine bay front cooling
Engine air intake Hot air from front of engine bay
Section PN
Hot air
from around
exhaust
system
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