Httpchk when server maxconn has been reached

Given the following configuration

listen input
    bind :80
    bind :443 ssl crt /ssl.pem no-sslv3
    mode http
    option forwardfor

    option httpchk /index.php
    http-check expect string 'test'
    server cookie ${x} check inter 2s ssl verify none maxconn 100

What happens to health checks when a server has reached the max 100 connections?
Does haproxy reserve a connection for itself to perform healthchecks?
Does it get blocked from making healthchecks?
In other works does ‘maxconn’ apply to ‘httpchk’?

I desire a configuration where healthchecks will always be performed even when the backend is at the ‘maxconn’ limit. That way the node is still performing some useful work.