haproxy setup is not working when resource utilization become high

We are using HA proxy v2.3 in our organization for load balancing our apache application servers. Three web application servers are configured in haproxy. When any one of the web application server resource utilization become high then the load balancing will not work. All the web requests will occupy in that high load server.Then the incoming requests will not equally distribute to other servers. So we will not able to access the web page.So at that time we have to edit the haproxy.cfg file and have to comment the high resource utilized server and will reload the haproxy service. Then only the application become up. Is there any option in haproxy.cfg file to overcome this situation? If the server load become high then that node have to skip and the request should pass to other nodes. The configuration is as follows:- global log 127.0.0.1 local0 log 127.0.0.1 local1 notice maxconn 4096 maxpipes 1024 nogetaddrinfo user haproxy group haproxy daemon tune.ssl.default-dh-param 2048 ssl-default-bind-ciphers HIGH:!aNULL:! MD5!eNULL:!EXPORT:!DES:!RC4:!3DES:!PSK defaults log global mode http retries 3 option httplog option dontlognull option forwardfor option http-server-close stats enable stats auth arun:arun@123 stats uri /haproxy timeout server 1200s timeout connect 20s timeout client 60s log 127.0.0.1:514 local0 notice default-server rise 1 default-server fall 20 frontend app_nodes bind *:443 ssl crt no-sslv3 no-tlsv10 no-tlsv11 reqadd X-Forwarded-Proto:\ https default_backend Application-nodes backend Application-nodes balance roundrobin server :80 weight 1 maxconn 2500 check server :80 weight 1 maxconn 2500 check server :80 weight 1 maxconn 2500 check log 127.0.0.1:514 local3 alert log 127.0.0.1:514 local2 info