We have not been able to get this unit working yet. The information did not say that this unit requires a 3/4 in gas line, while the old water heater only needed a 1/2 gas line. The information did not contain the information that a new large 4" hole needs to be cut into your roof for a larger exhaust. The information did not contain the fact that you need a new sewer drain for the condensate from this unit. It will take years to recover the extra cost for all this extra work and plumbing. If you think that installing an instant hot water heater is easy and will save you money. THnk again.