Freshwater system/pressure issues

[chuck g]

I installed a new Whale freshwater pump (UF0815) rated at 2.2 GPM a year ago, expecting that it would give me plenty of power for my two faucets and occasional showering on my 36-foot sailboat. It seemed to work fine last season, but during the winter I added a hot-water check valve and things have deteriorated.

Since adding the check valve, I am typically greeted with an explosive burst of water and air when I turn on the main galley faucet, located just a few feet from the pump. Rather than a smooth flow of water, it is intermittent at best even with the pump activated well in advance.

Among the things I have checked/considered:
-water tanks are full
-the strainer that came with the pump is clean
-I've considered adding an accumulator tank, although my reading suggests that should not be necessary with a modern pump
-I've removed my water filter from the line
-I'm wondering if my 35-year-old galley faucet could be the culprit and plant to check the faucet in my head to see if the same problem occurs

Any advice in troubleshooting and/or improving the problem would be greatly appreciated.