there is no accumulator tank on these modern units,
unless installed as aftermarket.
IF the pump is cycling at ALL, there is a leak somewhere.
this leak could be ANY place in the pressurized system...
from the external hose/faucet to any internal fixture/pipe/joint and so on...
could be at the water pump or at the water heater too.
for example IF the water heater is left ON and the pump is ON,
the pressure/temp relief valve on the tank will burp/drip occasionally.
this is almost a routine finding IF the water heater is on 24/7.
and the pump will cycle to restore the crucible water...
leading to a routine of 'drip/fill/heat/drip'
but ANY thing in the freshwater circuitry could be leaking...
filters, pump prescreen, pipes, joints, back flow valves, shower, plumbing, toilet and so on.
i have not seen an acceptable "minimum" referenced for pump cycling...
but if the water pump cycles more that 2-3 times in a 24 hour period
the search for an open source begins.
all of the true things that i am about to tell you are shameless lies. l.b.j.
we are here on earth to fart around. don't let anybody tell you any different. k.v.