Interesting concept but there may be drawbacks to it.
Those are low water drain points for both hot and cold. Under pressure you will probably get more cold water than hot because the cold is closer to the pump than the water heater.
Be ok for hot summer days but it will most likely be more cold than hot.
It would be easy enough to throw some hose on those valves and plumb the hoses to a faucet of some sort to see what evolves.
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