13
THE REMOVAL OF CONDENSATION FROM INSIDE THE INCUBATOR
Water vapour accumulates inside the incubator atmosphere from two sources, firstly from the evaporation
of the media in the Petri dishes and secondly by the hydrogen and the traces of oxygen being linked
together by the palladium catalysts. If this water vapour is not removed it will condense on the cooler
surfaces of the incubator walls and form pools of water. The cabinet however is fitted with a large
aluminium Condensation Plate which is kept a few degrees lower than the temperature inside the
incubator by a fan which blows cool air from the room onto its outer surfaces. This reduction in
temperature is sufficient to cause the excess water vapour inside the incubator to condense, run down its
surface and collect at the bottom and finally fall via a drain tube into the collection bottle situated inside the
cabinet. When this is full, remove it via the lock.
The fan for the Condensation Plate can be switched "OFF" at the Control Panel if the Service Engineer is
working on the unit. The humidity within the incubator is controlled by the Humidistat which is mounted just
above the inner door. The Humidistat switches the fan "ON" and "OFF" automatically.
THE GAS TRAP BUBBLE BOTTLE
The Gas Trap Bubble Bottle is mounted on the incubator endplate just beneath the Condensation Plate
and has several functions. Firstly, it is a safety device so that in the event of a gas Input Solenoid
remaining open, the gas has a way of getting out of the cabinet and not doing any damage to the structure
of the unit. Secondly, it allows the operator to be able to push their arms inside the cabinet without
applying undue pressure. It must be remembered that all gas that gets out of the cabinet via the bubble
bottle is wasted and therefore every effort must be made to minimise this when working inside the
incubator. If one arm is withdrawn as the other arm is pushed into the unit, gas wastage can be reduced.
THE HEATING AND GAS CIRCULATING SYSTEM
The heating and gas circulating system consists of one tubular 400 Watt heaters fixed directly behind the
fan units mounted on detachable plates in the top of the incubator. The fans run continuously whilst the
heater is burst fired.
THE TEMPERATURE CONTROLLER
An adjustable electronic temperature controller fitted in the control panel of the cabinet regulates the
temperature. The controller has a temperature sensor in the right hand top corner of the heating chamber
and the temperature of the incubator can be adjusted between 3 degrees C above ambient to 40 degrees
C. There is a green led incorporated in the temperature controller which indicates when the heater is
operating and a temperature display to give an accurate reading of the internal temperature of the cabinet.
A data sheet covering the temperature controller is included with this documentation.
.
