Just had a new HWHeater (gas) in home. Code required separate PRV exit line and an drain line for the pan also which were plumbed to the outside at least 6" above the ground. Two drain lines for pan and PRV. And now I need to replace a HWH in a condo where HWH is located on second floor sitting in a pan only ( no drain line at all). So now in order to meet code I will need a pan with a drain to the outside and a drain line for the PRV and the same for the PRV. So now the problem comes about=no way to pipe anything to the out side because of the configuration on the way the condo is built. I do have an attic but this is not going to allow me to place the exit drains only 6" above the patio and no exterior pipes allowed except at ground level for drains (6"above patio). So I was looking into a floodstop unit which will shut off the water if it senses any water in pan. I have one installed for the clothes washer which seems to work well whenever I run a test on it (turns off feed water lines). BUT THE CONCERN I HAVE AND HAVE GOTTEN NO REAL ANSWER THAT I THINK IS VALID (have talked to several plumbing companies, plumbers, etc) IS WHAT HAPPENS IF THE HWH LEAKS AND THE FLOOD STOP DOES ITS JOB OF TURNING OFF THE WATER AND THE GAS IS STILL ON. WILL IT CONTINUE TO FIRE UP WITH LITTLE OR NO WATER IN THE TANK CREATING A FIRE HAZARD?SO EMPTY TANK AND BURNER FIRES UP AGAIN AND AGAIN!!!YES OR NO? WHAT CAN OCCUR? NOT SAFE? IDEAS THOUGHTS WOULD REALLY HELP.......sewergas