Sediment Traps

Most manufacturers of gas-fired equipment such as a gas-fired heating system require a sediment trap (or dirt leg). The sediment trap protects the appliance from debris in the gas - such as dirt, soil, pipe chips, pipe joint tapes and compounds, and construction site debris that may enter the pipe during installation or repair.

Sediment traps are designed to cause the gas flow to change direction 90 degrees at the sediment collection point. The change in direction causes the contaminants to drop out of the gas flow.

The sediment trap utilizes a tee fitting. The nipple and cap must not be located in the branch opening of a tee fitting, because this wouldn’t allow the change in direction. Contaminants would pass right through the fitting and not drop out.

Three inches is commonly used as the length of the nipple.

The sediment trap should be downstream of the shutoff valve and within 6 feet of the appliance. This allows the trap to be serviced after the valve is closed.

This is a picture of a sediment trap that does not change the direction of the gas flow. Improper installation.

In my area a sediment trap is not required on a gas line coming from below.
The hillybillies in my area call them drip legs instead of sediment traps.

That looks like a regulator Ben.

Here’s a picture of an improperly installed sediment trap/drip leg.

Drip leg.jpg

Not required in Knox , I Mention it . Because that is only one county, I am not a code keeper. But i did have My gas fitter Lic, for 23 years in Canada.

My finger is on a regulator.
The arrow is pointing to an improperly installed trap.

Here’s another:

Ah, now I see it. . .

Does anyone actually service the trap? How often is it recommended?

Not in your lifetime. :mrgreen:

That’s what I thought! My lifetime is more than half over, and I’ve yet to see one being serviced. :shock::wink:

“more than half over”
So you must be around 60. ?
(btw -

Funny guy!!! :roll::smiley:
(btw- did you get my reply email the other day)?

I mean that I’m assuming you’re shooting (just as I am) for 120 years old before kicking the bucket. :slight_smile:

I’ll be happy if this “over-abused” body makes it to 80! Mentally, I’m still 28!! :cool:




No sediment trap leg/extension installed.
No shutoff valve installed.

No t&p relief valve piping either! Sorry could’nt help myself.

Not enforced, should still be noted by every inspector. Just cause the downhome boys in the field will ok it don’t make it right. No installations which fail to meet manufacturers recommendations are proper.

Fingers crossed and hoping it doesn’t blow up?

Good point.
The crossing of my fingers is a little clue to myself.
Most of my pictures have my hand in them. A “crossed fingers” is something wrong, bad, missing, etc.
ben-fingers-1.jpg TWO-hundred amps

ben-fingers-2.jpg Thumb in the direction of hot water from the boiler

ben-fist-3.jpg Checked for loose tiles in shower