It can sometimes take 10~20 minutes, especially with a new RV as you may have residual material in the lines from the mfg process.
If the water continues to be cloudy, your water system could be sucking air. Check the antifreeze port to make sure the cap is on tight. Especially if the dealer winterized it, they might not have put the cap on tight.
In Thor's never-ending effort to be cheap, they don't put a valve in the antifreeze port, but rather - just a cap.
Look for the cap in the area of the water pump.
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