Originally Posted by gfarmcafe
What I don't understand is why he's getting hot water for a very short time and then going cold. That tells me water is getting into the tank thru open valves and is being heated. Not warm, but truly hot!
With the valves not in their correct positioning, Cold water, via water pressure, is allowed to cross over and mix into the Hot water side causing spurts of "hot" and then "cold" water flow when in use.
When your water flow is idle in the HW tank and not interrupted by turning on the faucets, etc., the water in the tank will reheat and then when needed it will flow out first as hot, and then back to cold again. It will only keep repeating this process until the valves are in their corrected position.
Need to make sure the valves are in their correct summer mode.
When we had our previous HTT we ( newbies then ) had to learn the hard way as well. We had the SAME issue. Once corrected...we were good to go.