QUICK ANSWER YES. AS IN A COMBI BOILER THERE IS A RESERVE TANK [ A FEW LITRES] THIS CAN DO SMALL JOBS FOR A WHILE OR KEEP IT WARM SO IT WILL NOT TAKE SO LONG TO REHEAT. EVEN FROM COLD IT ONLY TAKES A FEW MINUTES TO HOT WATER SO AS THE WATER STARTS TO COOL AND DROPS TO CERTAIN LEVEL THE BURNER WILL S...