Direct Vent Furnace Venting Downhill

[dtontarski]

Reuben -

As Mike explained, and as the IRC cite that you included spells out - the key words are "sealed-combustion system". Just taking all combustion air from the exterior does not make an appliance a direct vent appliance.

By-the-way, if you look closely at the photo in my original post, you can see that the side combustion air port on the furnace cabinet has been used, but that the installer never sealed the optional top combustion air port. This furnace is therefore not drawing "all" of its combustion air from the exterior, and therefore it cannot be "strictly" defined as a direct vent appliance and therefore is not allowed in this closet. There was just too much wrong with this installation for me to talk about in a single post. I should have chimed in before Mike did on this...sorry for not doing so.

[inspectorreuben]

By-the-way, if you look closely at the photo in my original post, you can see that the side combustion air port on the furnace cabinet has been used, but that the installer never sealed the optional top combustion air port.

Good point - I didn't notice that.

- Reuben

[dtontarski]

Mike -

You type quicker than I.

Reuben - what Mike said.

I've got to learn to type faster.

[Terence McCann]

By-the-way, if you look closely at the photo in my original post, you can see that the side combustion air port on the furnace cabinet has been used, but that the installer never sealed the optional top combustion air port.

Hi Dave:

Did you pull the front panel to look at the combustion air piping? All the 95% I've seen are hard piped to the fan with a sealed combustion chamber (then the extra opening in the cabinet really doesn't mean anything). The condensate line needs to be trapped as well.

I just downloaded the picture to my desktop to blow it up and have a look-see. The installation of the hot water tank is messin' with my head. Tell me if I'm seeing this right.

The furnace and hot water tank are sitting on a raised OSB floor correct? That is a standard hot water tank that sits on feet with an open area underneath for combustion air (same one I have in my condo). It looks like someone dropped the hot water tank through a hole in the OSB flooring - is this correct? What is below the OSB flooring? Looks like a pipechase but how deep is that area. That's a really strange installation (I'm wondering how safe). How is it getting combustion air?

[dtontarski]

Terry -

I pulled the cover and this combustion air inlet in the side of the cabinet is just that - no pass through, nor direct connection within the cabinet. (unlike my own Trane 95+ unit that have a connection within the cabinet)

The water heater is installed flush on the surface of a raised 3/4" plywood floor. Buy hey - at least it's not installed on shag carpet.

Short of some type of elaborate run of combustion air to this bedroom closet (in the center of the home) and the installation of an approved door, I can't see how this CAT I water heater can remain. I suggested they consider an electric water heater.

Right now the combustion air is coming from 2-sources - through the louvered closet doors and whatever it can suck away from the furnace that doesn't currently have a sealed combustion system, as the optional combustion air inlet on the top of the cabinet is not properly sealed.

Sorry to messin' with your head.