In every cleaning system, you only have so many btu's available to heat your water. Kerosene is the hottest and unassisted coolant exchangers is the coolest. Engine coolant and exhaust/blower combinations are in the middle. Your blazer uses the engine exhaust and blower exhaust to heat your water. Your 18hp motor and #3 blower can only provide so much heat and if you exceed that capacity your temperatures will drop at the wand. The manufacturer recommends a 3 flow for best performance. The problem with a 3 or 4 flow is that it takes a long time for the hot solution to exit your hoses and wand and come up to maximum temperature. Every time you let off the trigger, the solution is cooling down in your hoses. I have found a 6 flow works best but if you have the trigger on continuously, you will experience a cooling of the solution. I would start in the middle of a room and clean to one side, then dry vac back to the center and repeat on the other side. A 6 flow will come up to temperature faster than a 3 or 4 flow but it is not sustainable for too long. Modify your cleaning techniques to reflect this.
