A little off subject and does nothing to answer the OP's questions...... but important to someone reading this thread and thinking about converting to gas tankless from tank water heating. TECO has a great rebate program:
Conservation Rebates - Peoples Gas
Over the last several years we have received $1000 total in 3 checks.
1. $100 new gas stove (I installed)
2. $400 new High Efficiency Tank Water Heating (I installed)
3. $500 new gas furnace as part of new HVAC System (Chuck Farrell installed and filled out paper work - I got the check)
