Bosch is always trying to upgrade its units and keep up with the energy efficiency ratings for higher standards. The Bosch Therm 330PN LP has been discontinued and is no longer made and is out of stock. The Bosch 330PN LP was discontinued as it did not meet the required energy efficiency regulations.
Bosch is working on new gas tankless models that will be more efficient and have better ratings.
Please call GlobalTowne at 888-726-9752 for help with replacing an older Bosch 330PN LP or one that used to take 4" venting going vertical through the roof.