I have a gas water heater located in a corner of my basement in Georgia. The vent goes out the top of the WH into a short S bend (8″)and then up through the first and second floors and out the roof. The WH is badly located for room renovations and I would like to move it about 15 feet into another section/corner of the basement. Utilizing the same vent is it permitted to run a horizontal(slightly elevated along the distance) vent tube along the ceiling rafters in the basement over to the existing vent port?
There are two types of vent pipes used for natural draft water heaters – single and double wall. Both of them require 1/4″ per foot pitch between the WH and a chimney flue connection (always going up towards the chimney).
- For the single wall pipe you need at lest 6″ clearance from framing and other combustibles, and max horizontal run must be smaller or equal to 75% of total vertical height. All joints fastened with screws and properly supported.
- Double wall pipe (B-vent) requires 1″ clearance, and you can run it horizontally up to 100% of your vertical pipe – don’t use screws on this one except for the draft hood connection (it has special locks at each end) – if it is concealed inside the wall / ceiling – you have to use double wall type vent.
Keep the number of offsets and bends (S-bend?) to minimum because each one lowers capacity of your chimney. Other option is going through the side wall with an induced draft / PVC vent water heater.