sediment trap

[jclark1]

If a NG furnace is being fed from below, does it still need a sediment trap (if required by jurisdiction)? Doesn't seem like it would, right?

[Larry D. Kage]

I'm thinking you would want one after it goes horizontal toward the furnace cabinet but I'm not for sure.

[jclark1]

The horizontal portion is only a few inches. I don't know why but today's inspection had a bunch of little things I'm not sure about. Just one of those days!

[Erby Crofutt]

(if required by jurisdiction)?

Kinda says it all right there, doesn't it??????

[jclark1]

Right Erby, but just because a jurisdiction normally calls for a sediment trap doesn't mean one is needed when the furnace is fed from below. If the pipe comes from below directly into an elbow and then enters the furnace housing, where would you put a trap? The only horizontal section of pipe is in the furnace housing before it goes into the valve. It seems to me in this case, a trap is unneccesary.

[Erby Crofutt]

How about at the end of the last horizontal run before the pipe goes vertical?

If the jurisdiction requires it, you need it.

How much simpler can it be said??

If the jurisdiction requires a house be no more than 35" tall, you won't be allowed to build a house any higher than 35".

Read the Fuel Gas Code and you'll figure out where to place it. The pipe doesnt' come out of the ground vertically into the furnace. I don't have the code handy but thought it said something like "

shall be installed as close to the inlet of the equipment as practical."

Where's the last horizontal run??

[jclark1]

actually it makes sense to have a trap at the bottom of the vertical run. Change the elbow to a tee and the sediment has somewhere to accumulate. The whole reason for the trap in the first place. Took a minute to get that through my thick head!