noob - Sparge Temps????

I just finished my first All-Grain brew and it went great. I made Edworts Haus Pale Ale. So now that I have made one all-grain I have been scouting out my next recipe. I have found a recipe I want to make but they do not provide the sparge water temps. I know you don't want to be warmer than 170 but is there a rule of thumb when it comes to sparge water temps??? ,

Here is the recipe:

OG = 1.052 FG = 1.016 IBUs = 28 to 30

Ingredients:

7.5 lb. pale malt
1 lb. caramel malt (60° Lovibond)
0.5 lb. toasted pale malt (toast the malt on a cookie sheet for 30 min. at 350° F)
4 AAU Cluster hop pellets (1/2 oz. of 8% alpha acid)
4 AAU Cascade hop pellet (1 oz. of 4% alpha acid)
1 oz. whole Cascade hops
American ale yeast (Wyeast 1056 or White Labs WLP-001)

Step by Step:

Mash 7.5 lbs. pale malt, plus the caramel and toasted malts in 3 gallons water at 152° F for 90 minutes. Runoff and sparge with 4 gallons.

Add Cluster hops, boil 30 minutes. Add Cascade pellets, boil 30 minutes. Turn off heat, add whole Cascade hops (in hop bag), steep 30 minutes and remove.

You will actually find that many people on this forum will recommend sparging even hotter. At least 180-185. The reason is that the hotter water will allow your overall grainbed temperature to equalize at or above 170. As long as your overall grainbed temperature doesn't exceed 180, you will be fine.