Thanks, cdafd, I looked in NFPA 13 8.3.2.5 and that section was very helpful. My sprinklers will have to be within 7 feet of the heat source so I'll bump the sprinks up to 286 deg.
How far away should I keep the fire sprinklers from an outdoor, surface-mounted heater? These heaters will be installed in the outdoor patio areas on a house but there is nothing in 13D that describes this particular appliance.