rgano
Guru
- Joined
- Oct 8, 2007
- Messages
- 5,152
- Location
- Panama City area
- Vessel Name
- FROLIC
- Vessel Make
- Mainship 30 Pilot II since 2015. GB-42 1986-2015. Former Unlimited Tonnage Master
If a 30 amp shore power line does the job I recommend the 3.5 Nex Gen, it has great load starting performance as it has a 5KW alternator but only has enough HP to produce 30 continuous amps, no brushes so no alternator maintenance, extremely smooth as it has a counter rotating set of balance shafts in the Kabota diesel,all service is done from one side of unit and its a low flat profile which may or may not work for you, it runs at 2600 rpm if I remember ?. I have one on my 26 foot LRC, perfect unit for me, a fraction of the cost of NL units and weigh much less , I have the factory sound enclosure, great option. 1/2 load fuel burn is .2 GPH that's my AC for 5 hours on one gallon of stinky stuff!
I have found that the 3.5 has its limits in the 90-degree water we experience here in the summers. Above about 22 Amps it overheats above its 225 set point and shuts down (using IR thermometer on the heat exchanger's side). There is no circulating pump for the coolant meaning it is naturally circulating, and Nextgen tells me it is thermally stable at around 210 degrees F. When mine first overheated earlier this summer running my 10 KBtu and 13.5 KBtu air conditioners simultaneously, I called NextGen. The temperature while running just the 13.5 KBtu AC was around 218 degrees with no thermal shutdown. NG suggested running Barnacle Buster through the seawater circuit as some of their south FL customers did three times a year to keep theirs cool - mind you this generator was brand new out of the box August 2018 with only 70 hours when the incident occurred and is always run of freshwater after every run. That brought the running temp from 218 down to around 200 for the 13.5 KBtu AC, but it would still overheat when adding in the 10 KBtu AC. Don't get me wrong, I like this unit, but I think a 5 KW NextGen with a probably larger cooling capacity not running so close to its limits would handle this heat issue better. I was able to easily run both AC units on the generator in the fall and spring with cooler waters under the boat.