Gas Pressure (appliances, house, contractor)

[citizen2100]

I have been trying to replace a natural gas appliance and when I replaced it twice the pressure regulators on the new appliances would blow the release valve on the pressure regulators and then leak gas with two separate appliances with in a few weeks of each other.

When I called the gas company the call center said they would send a technician and I did not have to pay the 90.00 service fee if my appliance was not repaired.

The technician came over and tested the appliance and determined that the main valve was bad on my original appliance and the whole appliance had to be replaced. I asked them to test the pressure at the gas line that goes to the appliance and the technician just said I have a 2 pound gas regulator in my crawlspace and never tested to see what the actual pressure was at the gas line for the appliance.

I called the gas company again and they just said it was 7" water column for the gas line that was connected to the appliance then charged me the 90.00 service fee on my next gas bill even though the appliance was not repaired.

I then got a 0" to 10" water column natural gas manometer from a local store. Then I turned the gas off to the appliance and then plugged the rubber end of the manometer hose to the 1/8" inlet NPT tapping on the appliance being carful to make sure the needle stayed at zero after being connected. I turned the gas back on to the appliance and got 9" water column when the furnace was not running and when I tested it again it read 8" water column when the furnace was running.

The top of the gas regulator in the crawlspace says 2 pounds (55.56" water column) and steps that down to 7" water column or to 11" water column depending on what the regulator is set to so I am speculating that the main gas pressure regulator in the crawlspace is set to 8" and then when all gas appliances shut down the gas builds up by about 1" water column to the 9" water column reading.

Everyone says to call the gas company but when I say the gas company was not helpful they say to call a plumber.

Who should I call?

Can a licensed gas plumber adjust the main regulator inside the crawlspace or does the gas company have do this?

If I call a licensed gas plumber to adjust the gas pressure regulator and not the gas company can the plumber turn the main gas line off on the gas meter on the side of the house or does the gas company come over and turn it off?

I have a new Trane furnace and if the pressure on the main gas regulator was turned down to 7" water column it may affect this new furnace. Should I call the HVAC company that installed the furnace to check the gas pressure on the inlet NPT tapping on the furnace or could the same licensed gas plumber check the furnace?

[Starglow]

I would call the gas company back again and be more persistent. They own the gas meter and the regulator, so they will have to replace it if there's a problem with too much pressure. This is a separate issue from the appliance itself which is why you might be spinning your wheels. The gas company is focusing on the appliance and not your meter, so when you call back don't talk about the appliance....just ask them to test your meter and regulator. Gas isn't something to mess around with or things can go boom.

[Tabster]

Sent this to my husband and this was his reply:

I am Sorry that you are having so much trouble. I hope this helps.

​9 inches of water column is not above the maximum allowable pressure on a gas appliance. I would not adjust it.

If you want to adjust it you can use your manometer to measure pressure as you turn the adjustment screw at the line regulator. Try 1 turn at a time (counter clockwise), release pressure at your manometer and check pressure. Set your pressure for 7 inches of water column static pressure (while appliance is not running). The pressure should drop to no less than 5 inches of water column while the appliance is running.

Does your appliance require an appliance regulator? Many, if not all gas cooktops require one that drops the pressure to 3.5 inches of water column. If it is required but not installed that could cause problems.

Usually turning off the gas meter is not necessary because the regulator should have a shut off valve in front of it. You own everything downstream of the gas meter, so the gas company does not need to be involved for anything beyond the meter. If you are deciding between a plumber & HVAC contractor, the HVAC contractor is more likely to be knowledgeable about gas.

One other thing, I suggest when turning on your shut off valves, do so slowly.


Good Luck!