Low lager ferment temps

I have a fridge that I’m going to use to brew lagers in as soon as my new freezer arrives for kegs.  I only have one temp controller that I plan put on the freezer to keep it at about 32 degrees or so.  But, if I use the fridge for lager fermenting, can I just set it at it’s highest setting and leave it there?  I expect that it will be far below 50 degrees even at a high setting.

Is there a downside from a flavour and quality standpoint to fermenting at lower temperatures?

I don’t really want to buy another controller because I don’t do many lagers and I was just going to leave the fridge unplugged and slightly open when not fermenting.  I was going to replace a small freezer and this fridge with the new, larger freezer but now I’m wondering if I should keep the fridge for this purpose.  If it’s not a good choice, I will send it to the recyclers. 
Thanks

The built-in thermostat will probably only get up to around 40°F. At that temperature, you run the risk of the yeast floccing out early, or not fermenting at all. It also probably won’t hold the temperature all that steady.

Serving temperature (~45°F) is pretty good for most lagers, so as long as there’s room you could always ferment them in the kegerator. At worst you’d just have to bump it up a few degrees when there’s something fermenting in there.

I was going to say that 32 is WAY to cold for serving. 32 is what you want to be able to achieve when lagering as I understand it. I would think you would want to use your temp controller on whatever you are fermenting/lagering in use the internal thermo or even a cheapo timer for the service cooler.

I would bite the bullet and pull the trigger on a controller.  You won’t regret the purchase and you can always sell it off if it’s not needed in the future.  There isn’t a really good workflow for fermenting lagers in a fridge without some modification of the actual fridge or an external thermostat.

Once you have the controller you can use it to ferment ales and hybrids as well when your environment gets too hot.  This gives you a lot of versatility.  Want to brew a Kolsch in the blazing heat of summer?  No problem.

I’ve fermented Bo-Pils recipes in the upper 30’s with great success, but I strategically raised the temp after the first 24 hrs by 1 degree per day until I reached 60 degrees, using my Johnson controller.

If you want to make great lagers, I highly recommend using a temp controller, as the fermention process is one of the most critical components in making that style beer. Nailing the fermentation is key to a great lager.