Why bother adjusting pilot?

Ken C.

I'm beginning to think that the pilot adjusting screw on gas valves is just a hoax .... every time I've tried to adjust the pilot using this screw, it has no effect. I'm not sure if turning the screw clockwise is supposed to turn the pilot flame up or down, but it seems to be moot. I'm turning the screw 5 or 6 complete turns, but nothing happens. I'm afraid to turn it more than that. One thing I have found that will improve a lazy pilot flame is disconnecting the pilot tube from the gas valve and blowing the tube out. The last time I did that, a cloud of dust blew out the pilot orifice, and the pilot flame was much better after that. But this adjusting screw just seems to be useless - or am I doing something wrong?

Robert O'Connor_7

Pilot......

What kind of gas valve was it?? Many incorporate a protective cap screw plug thing. Maybe you were just turning it??? Cleaning the pilot tube and orfice should be the first thing you do, before making a adjustment. Boc

Arthur

Pilot Adjustment

The pilot adjustment only gives a limited amount of adjustment. The main adjustment is the size of the pilot spud.
These vary is size depending on the gas (nat or lpg) and also on whether the pilot is heating a thermocouple or a thermopile. If the spud is very dirty the adjustment will not have much effect. The best way is to remove it and either clean it with an old toothbrush (I say old as pilot dust tastes yukky) or replace it with a new one.
Over the years I've found replacement for the little they cost to be the best way. Lpg pilots are usually marked 1 while Nat gas pilots can be marked 1.2 though to 1.9. Thermopiles need a bigger pilot than thermocouple otherwise they won't generate enough current.

lchmb

just a suggestion

The best laid plan can be the most costly..I would suggest you put the cap back on and leave it be. A pilot adjustmant is just used to reset from natural gas to propane when the unit is converted. When done you also have to change the orifice...as to taking it apart and cleaning it out..if this unit is a vent free you can damage the orifice and cause yourself harm..As to lazy pilot's..it is possible if the unit is older that the pilot assembly need's to be replaced. If you are having issue's with pilot outage's have a certified tech come in and check the assembly and the thermocouple or thermopile and safety's on the unit...

Unknown

Ken C.

I really want to help you as I know you are trying to learn. I am going to give you some information but I would like you to get in touch with me as you need some formal training. Call me at 401-437-0557.

Now here is the deal on pilot adjustment screw. Its purpose is to adjust the flow of gas to the pilot. The orifice is sized in the pilot to match the gas pressure for either natural gas or LP. LP orifices are smaller than natural. They come in different sizes to match up with the size of pilot required for each piece of equipment. Orifice sizes for natural gas .014 to .026 for LP gas .008 to .013.

The cap that covers the pilot adjustment screw can be removed then engage the screw screwing down (clockwise) will decrease flow, screwing up (counter clockwise) will increase flow. There is a sweet spot which must be reached in order to see any effect on the flame. The flame should be adjusted to a soft blue flame, hitting the upper 1/2 to 3/8 of the sensing element (thermocouple or pilot generator) the flame should be adjusted with a millivolt meter attached to determine maximum millivolts. For a thermocouple it should be 25 to 30 millivolts for a pilot generator it should be 750 millivolts. Do not be afraid to screw down until you see a change. The tip of the thermocouple should be a "dull red" a "cherry red" is too sharp and will damage (weld) the tip.

The proper way to clean a pilot is to remove the pilot and break the tubing nut, gently remove the orifice and blow the dust and dirt out you can do this with your own breath or use compressed air, do not use any thing metal or wood as that can damage the orifice.

This is just the tip of the iceberg in learning about pilots. If you can not attend some training classes with me you need to get some of my books. I will however always be here to help you.

Unknown

Corran Vincent

our orifices a sized different here in US than in New Zealand.

Arthur

Pilots

Do you mean to to say the pilots assembies are different too. The assembies we use are mostly Italian but they seem to look the same as the ones you have in the pics.
The Honeywell or the Robertshaw pics certainly do?

Unknown

The pilots may look the same but -

each one has its differences.

gas man_5

pilots

Just wanted to mention - any problems w/pilots- first you should clean them,never just throw in a thermocouple , if pilot goes out again , you should check the gas pressure,and then you can look further! once cleaned ,check pressure before going to adjustment !