Replacing GPIB device with RS232 device

I have an antiquated Belhman power supply that is GPIB controlled. This device is failing. We have equivalent Belhman replacement power supplies that have only an RS232 interface.

Can I use the GPIB to RS232 converter to effectively control the RS232 replacement power supply? 

Can the code remain as is unaltered? Below is an example of the Belhman initialization code in "C".

int InitBehlman1350ACPwrSupply ()
/* *********************************************************** */
/* This function initializes the Behlman 1350 AC Power Supply */
/* returning a PASS if the initialization was successful and */
/* a FAIL if unsuccessful. */
/* *********************************************************** */
{
int fail_flg, BOARD, gpiberr, reterr;
char ACPSBUFFER[71];

fail_flg = PASS;
FillBytes (ACPSBUFFER, 0, 71, 32);
BEHLMAN = OpenDev ("BEHL1350", "");
if (BEHLMAN > 0)
{
gpiberr = ibwrt (BEHLMAN, "CNF", 3L);
fail_flg = GetBehlmanACPSStatus ();
if (fail_flg == PASS)
{
gpiberr = ibwrt (BEHLMAN, "IST", 3L);
fail_flg = GetBehlmanACPSStatus ();
} /* end if */
}
else
{
reterr = MessagePopup ("BEHLMAN AC POWER SUPPLY ERROR","ERROR - DEVICE NOT OPEN !!");
fail_flg = FAIL;
} /* end if */
/* ***{ RESULTS }*** */
return (fail_flg);
} /* end function */