I would not try it. Lagers are more of an advanced brew and you really need to be able to control your fermentation temperatures. The yeast will probably do some kind of fermentation at 17 but it won't be very good. The yeast will be stressed and give you off flavors.
What you could do is get a clean ale yeast like safale us05 and use it. Ferment that at 17 for around 10-14 days and you should have something tasty.
Also trý and post up a biabacus file with rhw recipe and your kettle dimensions and we'll help you have the best brewday possible.

You will want to ferment that one at 65F. With your options, start at 62.6F for the first 6+ days, then move to a warmer spot from about 8 days. 21 days would be the outer limits, if you are doing this just on weekends.
MS

For mine, that is coming out today or tomorrow, mine stopped fermenting after 16 days using US-05.

Christin,

The advice given by Lumpy and MS was good, as lower to mid 60F range is normal ale temperature range. And I brew lots of lagers, almost always fermenting temperature controlled at 50 deg F.

HOWEVER...Marshall from Brulosophy.com does lots of brewing experiments. And one of his recent "exbeeriments" was using that same Yeast you wanted to use at higher and lower temperatures. And he reported that people could not reliably distinguish the finished beers apart. It's an interesting read. I have not done this myself yet, but based on that would give it a shot.

Link: http://brulosophy.com/2016/02/08/fermen ... t-results/

If possible, try to keep your fermentation temperature CONSISTENT. If you had room to place the fermenter in a garbage can with water...to keep fermentation temperature consistent. In a crawlspace you may not have enough room for that. Old blanket or two, maybe. (?)

And as others have said, I also wouldn't be concerned with leaving it in the primary the entire 3 weeks. Do that myself. (Don't even use a secondary).

So if you want to try brewing a Lager, I would give it a shot. And please - let us know how it goes!