We study the effects of accretion environment ( gas density , temperature , and angular momentum ) at large radii ( \sim 10 pc ) on luminosity of hot accretion flows .
The radiative feedback effects from the accretion flow on the accretion environment are also self-consistently taken into account .
We find that the slowly rotating flows at large radii can significantly deviate from Bondi accretion when radiation heating and cooling are considered .
We further find that when the temperature of environment gas is low ( e.g . T = 2 \times 10 ^ { 7 } K ) , the luminosity of hot accretion flows is high .
When the temperature of gas is high ( e.g . T \geq 4 \times 10 ^ { 7 } K ) , the luminosity of hot accretion flow significantly deceases .
The environment gas density can also significantly influence the luminosity of accretion flows .
When density is higher than \sim 4 \times 10 ^ { -22 } \text { g } \text { cm } ^ { -3 } and temperature is lower than 2 \times 10 ^ { 7 } K , hot accretion flow with luminosity lower than 2 \%L _ { \text { Edd } } is not present .
Therefore , the parsec-scale environment density and temperature are two important parameters to determine the luminosity .
The results are also useful for the subgrid models adopted by the cosmological simulations .