BeerBorg

I've had to reheat the mash 2-3 times, because the temp goes too low. I usually heat the strike water 7 degrees higher, and wrap the pot in a sleeping bag. I stir every 15 mins, so this is when the temp drops. I was thinking of preheating the oven to try and maintain the temps.

Has anyone tried this?

Are you doing this in a Mash Tun, BIAB, pot on stove?

Yep. Was able to maintain very even mash temp that way. Here's what I did.

Get water to strike temp on stove and mash in.
Preheat oven to 170* (that is my lowest setting).
Turn off oven.
Put pot in oven.
Stir every 15 minutes, and check temp.
Turn oven back on to 170 if needed and turn it off again.
Lather, rinse, repeat.

Worked like a charm for me.

The lowest my oven goes is 250, but I have a really good thermometer so I could shut the thing off when it reaches 170. I'm using a 5 gal pot

I do what GWCR said, and it works great for me.

I do the same. Try "warm" on your oven. Remember that warm air is slow to heat the much denser wort. My 170 oven doesn't warm my mash at all, but keeps it from cooling.

My oven has a digital control that is accurate, and the lowest setting is 150*F, so I just preheat it to 150, then when i mash in i just stir for a couple minutes and put the pot in the oven, stirring every 15-20 mins until the end of the mash.

I have a harder time LOWERING temps here in FL , I BiaB on my grill and wrap in fender covers and usually my temp won't come down.