[LadeeDIY]

Have a second floor unit (725 sq ft) in a 3 story building. It's about 20 feet up to the roof where my flue winds up. I have a very old gravity wall furnace (natural gas) which gave out a few weeks ago. Tried to fix, but dead.


Want to keep using the natural gas. Mini split install is out of my price range (quoted 8K - 10K purchase/install). All HVAC contractors I talked to say this is my best option. Am in WA state. Don't need AC. :vs_whistle:

Is my only option a gravity wall furnace? I saw some sleek looking direct vent natural gas wall heaters online and some ceramic natural gas radiators. Will direct vent work if I use the same flue that is on roof? Have space for 45 or 90 angle vent from wall furnace to flue.



If not, horizontal direct vent is ok though prefer vertical. How much open space for safe CO discharge needed? It's a high density urban environment though there's open air for 15 feet diameter outside the building.



I need this permitted by the city. I can do some of the work but don't have contractors license. That's required to pull permit.

 

[sktn77a]

Direct vent usually requires a dual flue (combustion air supply and combustion fume venting). If you can replace your existing flue, they should work fine. If not, there are plenty of new gravity wall furnaces that should work just fine too.

 

[yuri]

Try get the install manual for the direct vent unit and it will have venting diagrams and minimum distances.

Some brands have manuals online. The inspector will use the pics in the manual for reference.

Direct vent has one drawback. If the intake gets plugged with snow or leaves or spiders webs or debris then you have to climb up there to clean it out and need access.

Rare it happens but it can. The old school chimney one is probably more reliable that way.