Techimpex Oven - Opening at the rear

[umu]

Hi,
we tried a couple of times baking bread in the Standard Techimpex Oven, but the real Temperature measured inside (not on this useless thermometer in the door) only gets to below 200C.
I noticed that the oven has large holes in the back that vent into a rectangular bracket on the rear.
When I close this bracket on the top with e.g. some aluminium foil the oven gets to decent 220-230C which is sufficient for baking bread and it worked out fine this way.
However I have no clue what the intention behind these openings was in the first place or if I risk damaging the oven by effectively closing these rear vents.
Any opinions ?

[Rampage]

Obstructing the vents at the rear of the oven may well lead to incomplete combustion of the gas, leading to the production of Carbon Monoxide rather than Carbon Dioxide.  Deaths due to Carbon Monoxide poisoning happen all too often, so I really wouldn't obstruct the vent system on the over.  In addition, fit a Carbon Monoxide alarm if you haven't already got one, just to be on the safe side.