I hooked up a sidearm heat exchanger to my 50 gallon propane water heater. I came out of the bottom and placed a tee. Off the side of the tee a 2inch nipple to a elbow then a union. After the union my gravity recirc line tees in. After the recirc tee is a ball valve and then to the sidearm exchanger. In the end of the tee I screwed in a threaded well for the aquastat. On the top I pulled out the pressure relief and placed a stainless tee. Pressure relief was then placed back into the end of the tee and copper was piped out of the top of the tee and up about 12inches and then horizontal back to the top of the sidearm. My plumber installed a Watts mixing valve. On the gauge after the mixing valve it says the water is 130 degrees. Prior to doing all this when I turned on a faucet we had almost instant hot water. Now when we open the faucet it takes up to 4 min to get warm water. After a couple minutes of warm water it starts to get hotter. Heres the funny thing, after all this and 10 minutes of running hot water and shutting it off for 5 minutes and I turn it back on, the hot water is gone again and it takes minutes to get it back. I apologize for the confusing post. What am I doing wrong? Please help everyone in this house is mad?