I'm trying to install secondary burn to my squire insert. I have drilled a hole on the side and at the top of the stove. I installed a 3/4" black steel pipe at the top front of the stove with holes drilled downwards. I have a valve on the outside of the stove to control the air flow. I'm not getting any secondary burn. My stove might not be air tight so not sure if that's the problem. Any help would be great. Thanks