Dear Archana hi,
 
Follow below:
 
Step0 
Make sure you have no firewall between you (php server root ip) and the server that blocks requests.
 
If this is OK then:
 
Step1    
Inside postgresql.conf make sure you have set the listen IP and listen port of your server and this will be the port you connect with php pg_connect
 
Step2
Inside pg_hda.conf configure the hosts you will allow connection either as trusted or md5
 
Typically bellow will allow all to connect
 
hostnossl    all         all         0.0.0.0/0          trust
 
Below will allow all to connect using username and password (but before have the first rule enabled to create remotely the users)
 
hostnossl    all         all         0.0.0.0/0          md5
 
Step3    restart Pgsql server to grand the new setting.
 
BR,
From: pgsql-php-owner@postgresql.org [mailto:pgsql-php-owner@postgresql.org] On Behalf Of Archana K N
Sent: Monday, April 30, 2012 11:30 AM
To: pgsql-php@postgresql.org
Subject: [PHP] Cannot connect to remote postgres using php
 
 Hello,
        I am getting this error whenever I try to connect to remote computer.
 "Warning: pg_connect(): Unable to connect to PostgreSQL server: could not connect to server: Connection timed out (0x0000274C/10060) Is the server running on host "10.162.19.3" and accepting TCP/IP connections on port 5432?  "
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 regards
 archana
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