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mannye
Dec 12, 2006, 10:21 AM
I just ordered a new gas valve for my fireplace. I damaged my old one by blowing compressed air into it to remove spiders that had found their way in through the gas orifice to the burner.
Question: how do I test the water column pressure on the new valve, or do I assume it already comes pre-set from the manufacturer?

newaukumdon
Dec 12, 2006, 09:12 PM
The valve does not control pressure that would be done by the regulator at the gas meter or if propane, the regulator before the house. Should be 11 inches water column or 3-5 PSI to the valve.

I am not a gas expert and would check to see regulator PSI
Regards,
Don

NorthernHeat
Dec 13, 2006, 05:22 AM
There is a tap on the in and out of the gas valve. There is a pressure regulator inside it. You need a special gauge (magnahelic gauge) to adjust the output pressure. Most of the time they come preset pretty darn close to 3.5" W.C. This is pressure for Natural gas not LP is it?

mannye
Dec 13, 2006, 06:27 AM
Sorry, Newaukumdon, but I believe you are misinformed.

From my reading on the subject, the water column pressure can be tested on the gas (natural, not propane) valve by way of 2 screws (A and B) located above the pilot control knob. The inlet should read 7", and the outlet about 3.5" .

My question is if there is a specialized tool for this, or is there a an alternate way to check this pressure without the specialized tool/

Also, would the new gas valve (ordered from the fireplace manufacturer) already come pre-set to those pressure readings?

Perhaps a member in the HVAC trade would be able to respond to this.

newaukumdon
Dec 13, 2006, 05:11 PM
We build a heating unit that uses a Robert Shaw control valve and even now I am looking and the only adjustment I see is for the pilot. But I am not an expert NORTHERNHEAT seems to have this one covered.

Regards and good luck,
Don
PS The control units we get work great right out of the box

caibuadday
Dec 13, 2006, 06:19 PM
Sorry, Newaukumdon, but i believe you are misinformed.

From my reading on the subject, the water column pressure can be tested on the gas (natural, not propane) valve by way of 2 screws (A and B) located above the pilot control knob. The inlet should read 7", and the outlet about 3.5" .

My question is if there is a specialized tool for this, or is there a an alternate way to check this pressure without the specialized tool/

Also, would the new gas valve (ordered from the fireplace manufacturer) already come pre-set to those pressure readings?

Perhaps a member in the HVAC trade would be able to respond to this.
What about a clear plastic tube (U shape, filled with water) connect to the valve , use 1/2 plastic fitting... the pressure of the gas would push the water in the U section up the vertical section of the tube( WC)... just an idea...