I am narrowing down the quotes for a new gas furnace / AC system. One
installer is quoting a Lennox G61V and the other a Ruud UGRA series. One
uses a hot surface ignition; the other direct spark. I know that if made
well either can be quite reliable, but my question to all is whether there
is any data that shows the Lennox hot surface design or the Rheem/Ruud
direct spark system in these higher end models either performs better or is
any more reliable? Also, is one significantly more expensive to replace?