I had one of these in my shop here in Scotland and was advised by the man who fitted it never to put them in a recess as standing out on their own they will give out a lot more heat. I used to burn peat, which smelled lovely.
Also regarding the fireplace, be careful as KKOB says a lot are fake. A neighbour of ours had someone using his place and lit a fire, it started a fire in the bedroom, as the fireplaces in our group of villas are fakes and there to look nice.