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bplinder
12-06-2007, 10:11 AM
I recently installed a new A/C and furnace in my. It is the bryant evolution 90+ furnace. (I believe it is a 355AAV).
Anyway, the gas line does not have a drip leg. Actually, it didn't have a drip leg for the old furnace either, and the installer did not put one in. how important is a drip leg for a natural gas furnace? What exactly does it do?

Thanks for your advice.

woody19
12-06-2007, 11:54 AM
Code requires a drip leg to prevent any foreign particles i.e. cutting oil, metal filings, etc. from entering the gas valve. It should be installed upstream of the valve.

bplinder
12-06-2007, 01:58 PM
So this is code. Hmmm. Do you need a drip leg on every gas line (dryer,water etc), or is one drip leg good for the whole house near the meter?

Here is a picture of the install. Can he place it at the bend right before entering the furncace. I think you are saying that it has to go before the 1/4 turn valve, correct?

Thanks

dr unico
12-06-2007, 02:05 PM
^^ Up stream from the gas valve ??? I always put mine at the lowest point before it enters the appliance or at the bottom of a riser, gas fireplaces etc do not require a drip leg.

woody19
12-06-2007, 05:38 PM
^^ Up stream from the gas valve ??? I always put mine at the lowest point before it enters the appliance or at the bottom of a riser, gas fireplaces etc do not require a drip leg.

Upstream from the gas valve, downstream from the shut-off valve. Didn't make that very clear, thanks. Code per IFGC 408.4.

In the photo the drip leg, or sediment trap, should be located after the shut off valve at the location of the first elbow. It should have a tee fitting at that point instead of the elbow and a 6 inch "leg" capped at the bottom.

xersw
12-06-2007, 05:48 PM
Exactally what woody said at the elbow closes to you if your standing at furnace,change to a tee.

mikesands
12-06-2007, 06:44 PM
The drip leg is also used for catching condensation so I would put one on it if possible.

catmanacman
12-06-2007, 07:10 PM
drip legs at each appliance are not required in and around San Antonio they just put 1 at the gas meter we can also use gas flex just have to hard pipe out of furnace

woody19
12-07-2007, 10:28 AM
drip legs at each appliance are not required in and around San Antonio they just put 1 at the gas meter we can also use gas flex just have to hard pipe out of furnace

We always install them at each appliance rather than at the meter because debri can be in the piping after the meter ( and usually is). Just the way I have done it for years anyway.:)

hearthman
12-07-2007, 11:03 AM
Catman, sediment traps are required by code--just not enforced in your area. If there is an Ooops!, and it is found to be caused by foreign material in the valve where no sediment trap was installed, the installer will be held liable, inspection or no inspection. Just because your ahj does not inspect to or enforce every aspect of the code does not nullify the code.

Hearthman

howard33
12-07-2007, 12:37 PM
How is a flex gas line trapped then? After valve with a tee then into the flex to the appliance?

second opinion
12-07-2007, 01:42 PM
Catman, sediment traps are required by code--just not enforced in your area. If there is an Ooops!, and it is found to be caused by foreign material in the valve where no sediment trap was installed, the installer will be held liable, inspection or no inspection. Just because your ahj does not inspect to or enforce every aspect of the code does not nullify the code.

Hearthman

NFGC 8.5.7 Where a sediment trap is NOT incorporated as part of the gas utilization equipment, a sediment trap shall be installed as close to the inlet of the equipment as practical at the time of the equipment instalation.

NFGC 6.6.1 PROVIDE DRIPS WHERE NECCESSARY. For other than dry gas conditions. etc.:)

woody19
12-07-2007, 02:21 PM
How is a flex gas line trapped then? After valve with a tee then into the flex to the appliance?
Yes, it can be done that way.Flex cannot, however, go into the appliance. Ridgid pipe needs to come out of the furnace.

howard33
12-07-2007, 02:28 PM
I see; but you wouldn't have to do so for a gas water heater then since there is no housing to chafe (assuming that is the reason for the rigid pipe)?

woody19
12-07-2007, 05:58 PM
I see; but you wouldn't have to do so for a gas water heater then since there is no housing to chafe (assuming that is the reason for the rigid pipe)?

That is correct, unless otherwise prohibited by your local codes.

bplinder
12-10-2007, 02:42 PM
I just checked this out, and I have a drip leg right before the gas meter,and that's it. There are no legs for the hot water heater, dryer, furnace, and I don't know about the oven.
The furnace installer wasn't too keen on coming back to install one, but I'll try again.

How long does it take to install one, where the current configuration is an L-shape as pictured above?

woody19
12-10-2007, 05:04 PM
I just checked this out, and I have a drip leg right before the gas meter,and that's it. There are no legs for the hot water heater, dryer, furnace, and I don't know about the oven.
The furnace installer wasn't too keen on coming back to install one, but I'll try again.

How long does it take to install one, where the current configuration is an L-shape as pictured above?

Less than an hour.

mobileguy
12-10-2007, 07:13 PM
black iron tee - $.xx
3 black iron nipples - $x.xx
black iron cap - $.xx

Service call to repair/replace valve - priceless (+$x.xx & time for a dirt/drip pocket)!!

Many appliances spec a drip/dirt pocket in the supply piping for the appliance. Here specs supercede code so why not put them in? Just follow the instructions......

Our code up here; depth of pocket shall be either 3"/75mm in diameter or equal to the internal diameter of the piping which it serves, whichever is greater. Diameter of pocket shall be NPS 2 or the diameter of piping it serves, whichever is less.

I know it doesn't apply in your area, but its gotta be there for a reason.

Airhead84
12-10-2007, 07:19 PM
I always install drip legs as a rule, as for the nescessity of it, its arguable, but I install them anyway.

tunnel_rat
12-10-2007, 07:58 PM
When using flexible pipe such as Gastite, I have been told by inspectors, a dripleg by the Main at the manifold will be enough. I usually still put one near the appliance just to be safe.

skippedover
12-10-2007, 08:04 PM
NFGC 6.6.1 PROVIDE DRIPS WHERE NECCESSARY. For other than dry gas conditions. etc.:)

You've hit the key right there. "For other than dry gas....." In our area the gas companies provide nothing BUT dry gas and I'll bet that's the case across the entire country. So honestly, what quantity of water or debris have you ever pulled from a drip tee? Once I got a fist full of cutting oil but that was it in all the years I've been working on gas. Yes, we do install drips but that's more to avoid any unwanted conversations with inispectors who are old school but honestly, they're just a decoration, IMO.

Wheelbaron
12-10-2007, 11:45 PM
Like the man said just do it, it's only a few bucks in fittings. If possible I like to put in a new shut off to. Some of those old shut off valves are scarry, the brass handle ones that are spring loaded and always have crud oozing out around the stem....:rolleyes:

sammyray
12-11-2007, 12:31 AM
Not required in southeast Texas because the gas well is usually no farther than the back yard.:D

hearthman
12-11-2007, 12:43 AM
They are different. The sediment trap goes at the appliance whereas the drip is usually at the service entrance.
With so much documentation telling you to install them, to exclude them is insane. Screw the local AHJs--the codes require them and virtually all appliance mfrs. recommend them.

This should not even be discussed. Put them in. :confused:

Hearthman

sbrooksL
03-05-2009, 05:04 PM
^^ Up stream from the gas valve ??? I always put mine at the lowest point before it enters the appliance or at the bottom of a riser, gas fireplaces etc do not require a drip leg.

So gas fireplaces don't require a drip leg, why? It is good if they don't because the gas line installer did leave room for one.

approved101
04-17-2009, 05:36 PM
its is as per code and when in doubt better to be safe than sorry.