Blowing out moisture from gas line to furnace

[pauls340]

So, because of budget reasons when building the garage, I used 1/2" black pipe for the line from the house to the detached garage. Up the wall into the storage space is my furnace. Ten feet before the furnace connection I put a vertical drop cleanout or moisture trap. If I open the trap will I get most of the moisture out? I believe that moisture, every year at startup, causes a delay of the furnace to kickon that takes about 24 hrs. Is this normal?

 

[67Dart273]

Uh, WHUT?

I've serviced units the piping of which had been in place for 20-30 years, and had never been opened to "drain moisture." Unless you have a poor gas supplier, there should not BE much if any moisture in there

Do you actually GET moisture out of the trap?

Otherwise, this might be due to another problem. What kind of furnace, and what sort of ignition does it use?

That is, older standing pilot?

Hot surface, spark ignition?

Is if forced draft, IE has a draft motor?

All that "stuff" can complicate what goes on.

On the newer electronic stuff, the flame sensor is almost always what is known as "flame rectification." this involves a VERY tiny current of sometimes only 1 or 2 microamps. If the sensor probe is improperly located, corroded, and or has deposits on the ceramic insulator, or maybe the probe has a poor connection to the wire lead, they can be "fussy."

Many (most) newer furnaces have a diagnostics "flasher" on the board, which can help. Otherwise, you need to learn (or have someone) who can diagnose if the firing cycle is OK

 

[pauls340]

Thanks. Most of what you said is way over my head. Unfortunately, the "family" friend HVAC guy is a crackhead and nobody wants him around. I've not opened the drain in 5 yrs. I did blowout the 1/2" black pipe before I hooked everything up and all kinds of rusty blackish water came out. The underground black pipe sat for 5 months before I hooked up the furnace. The furnace has always kicked on, it just takes several hours. Would it take the low pressure gas from the house hours to get to the detached garage 75feet away? Thx

 

[67Dart273]

Gas pipe CAN accumulate "junk" inside, oil impurites, etc, but water, doubtful. If it did it would freeze up the meter and regulators.

"Several hours." You need to post a photo or two and brand / model of the furnace. Much more likely something wrong, right there

The pipe sitting there "for a year" or whatever should still have gas in it.......there's no place for it to go, LOL Sort of like air pressure in a tire