Need Help Figuring Out Pipe Size NG for Generator

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Great! Now, how can I figure out what my starting WC pressure is? I think you made an assumption we were starting at 8 inches. What's the best way to confirm what I am starting with?
Test it with a manometer.
 
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Does this change any of your calculations?

I found this on my utility's website:

2. Standard Delivery Pressures
Company will provide natural gas to all residential gas customers at approximately
1/4 psig delivery pressure (approximately 6 to 7 inches water column).
Company can provide natural gas to all commercial and industrial customers at of either 1/4
psig, 5 psig or 10 psig depending on load requirements and pressure availability.

The following table is a quick reference of the standard delivery pressures available
for the different type of customers in the Entergy Gas System:

Type of Customer: Standard Delivery Pressure

Residential ¼ psig (6-7 inches-water column)

Commercial ¼ psig, 5 psig or 10 psig

Industrial ¼ psig, 5 psig or 10 psig

If a pressure, lower than any of the abovementioned standard delivery pressures,
becomes necessary, it is the customer’s responsibility to reduce the pressure on
their fuel line or at the appliance.
 
Does this change any of your calculations?

I found this on my utility's website:

2. Standard Delivery Pressures
Company will provide natural gas to all residential gas customers at approximately
1/4 psig delivery pressure (approximately 6 to 7 inches water column).
Company can provide natural gas to all commercial and industrial customers at of either 1/4
psig, 5 psig or 10 psig depending on load requirements and pressure availability.

The following table is a quick reference of the standard delivery pressures available
for the different type of customers in the Entergy Gas System:

Type of Customer: Standard Delivery Pressure

Residential ¼ psig (6-7 inches-water column)

Commercial ¼ psig, 5 psig or 10 psig

Industrial ¼ psig, 5 psig or 10 psig

If a pressure, lower than any of the abovementioned standard delivery pressures,
becomes necessary, it is the customer’s responsibility to reduce the pressure on
their fuel line or at the appliance.
Your generator requires 7” minimum and according to your gas company they may only supply you with 6 but could be 7.

So if it’s 6 then you’ll need to call them and tell them you need 7 minimum but would like 8”.

If you only have 7”WC and can’t get it increased then you need to run 1” Pipe. That 1/2” hose x 12’ may be a problem too.

You need to find out the exact pressure you have and if you can get that bumped up. Usually it’s not a problem.
 
Got it! I will have a plumber bring a manometer and confirm the current WC, then follow up with the utility if needed. If the WC is less than the 7 required by the generator, do I have to wait for the utility to increase the pressure before running the 3/4ths pipe for the 70ft or can I go ahead and do that now? It's taken forever to get an appointment with a plumber, I'd hate to have to reschedule.
 
I’d check the pressure first. If it’s below 8 and it probably will be, I’d ask if they can bump it up.

If it’s below 7 then I wouldn’t install any pipe no matter the size. It won’t work to full potential.

If it’s 7 “ WC or a little above then I’d install 1” pipe.

8”wc or above and I’d go 3/4”
 
Just because I'm detail oriented, I'd find the nameplate ratings on the other appliances, so in the dead of winter when your heat is running on the generator and you go do take a shower, your tankless hot water heater doesn't starve your generator and everything falls over....
 
Just because I'm detail oriented, I'd find the nameplate ratings on the other appliances, so in the dead of winter when your heat is running on the generator and you go do take a shower, your tankless hot water heater doesn't starve your generator and everything falls over....

Did you read the thread from the start ?
 
Did you read the thread from the start ?
Umm,yeah. You mean the OP's statement that he didn't have all the details:
/*
My stove top, clothes dryer, and on demand water heater are on gas. It's possible that gas is also tied into my central air and heat but I'm not positive on that.
*/
Or your recommendation that he check the nameplates? Sorry I didn't credit you with the original recommendation.
 
Umm,yeah. You mean the OP's statement that he didn't have all the details:
/*
My stove top, clothes dryer, and on demand water heater are on gas. It's possible that gas is also tied into my central air and heat but I'm not positive on that.
*/
Or your recommendation that he check the nameplates? Sorry I didn't credit you with the original recommendation.
I figured since you were detailed oriented that you would’ve read the thread.

No worries, it’s nothing about credit.
 
I’d check the pressure first. If it’s below 8 and it probably will be, I’d ask if they can bump it up.

If it’s below 7 then I wouldn’t install any pipe no matter the size. It won’t work to full potential.

If it’s 7 “ WC or a little above then I’d install 1” pipe.

8”wc or above and I’d go 3/4”
Ok, I had a gas line plumber come out. Their plan is to run a 1 inch pipe 70 feet and install two new regulators, a new one for the house, and one near the quick connects towards the end of the 70ft run. They would also file for the permits with the city and coordinate with the utility to change out the meter. My issue now is that it is not a good time for me to fork over the $6k+ I got quoted. I'm not saying it is not worth it, I just did not anticipate it being that expensive. I was thinking around $3k. How expensive are these regulators?
 
Ok, I had a gas line plumber come out. Their plan is to run a 1 inch pipe 70 feet and install two new regulators, a new one for the house, and one near the quick connects towards the end of the 70ft run. They would also file for the permits with the city and coordinate with the utility to change out the meter. My issue now is that it is not a good time for me to fork over the $6k+ I got quoted. I'm not saying it is not worth it, I just did not anticipate it being that expensive. I was thinking around $3k. How expensive are these regulators?
They cost less than $100 each.

I’d get another quote or two. 6k is way too much. IMO 3k is too much.

It’s a days work for a plumber and helper with about $650 in material.
 
I just came across this thread. Not sure why I missed it in the first place. I bought Firman Tri-Fuel portable generator from Costco. My plan is to use it outdoors during power outages and at other times, store it in the garage. I got electrician to install interlock on the main panel and got a plumber to hook up a natural gas shutoff valve with a quick connect for a hose connection to the generator. Reading this thread, I think I overlooked lots of details. I already have two central gas furnace units, one gas heater for the pool and a gas grill converted and connected to natural gas as well. No consideration for meter capacity or pressure was given. So, I will follow what is suggested in this thread and talk to the gas company first. I am glad I came across this thread. Thanks to all.
 
I just came across this thread. Not sure why I missed it in the first place. I bought Firman Tri-Fuel portable generator from Costco. My plan is to use it outdoors during power outages and at other times, store it in the garage. I got electrician to install interlock on the main panel and got a plumber to hook up a natural gas shutoff valve with a quick connect for a hose connection to the generator. Reading this thread, I think I overlooked lots of details. I already have two central gas furnace units, one gas heater for the pool and a gas grill converted and connected to natural gas as well. No consideration for meter capacity or pressure was given. So, I will follow what is suggested in this thread and talk to the gas company first. I am glad I came across this thread. Thanks to
I just came across this thread. Not sure why I missed it in the first place. I bought Firman Tri-Fuel portable generator from Costco. My plan is to use it outdoors during power outages and at other times, store it in the garage. I got electrician to install interlock on the main panel and got a plumber to hook up a natural gas shutoff valve with a quick connect for a hose connection to the generator. Reading this thread, I think I overlooked lots of details. I already have two central gas furnace units, one gas heater for the pool and a gas grill converted and connected to natural gas as well. No consideration for meter capacity or pressure was given. So, I will follow what is suggested in this thread and talk to the gas company first. I am glad I came across this thread. Thanks to all.
Don’t run the pool heater when the generator is running and it’ll probably work fine.
 
Thanks. Makes me feel better. We rarely use the pool heater. Also, the plans are not to fully load the generator. Just run some essential things such as refrigerators, some lights, computers and perhaps a tv. Not expecting to have all creature comforts during the outage.
 
They cost less than $100 each.

I’d get another quote or two. 6k is way too much. IMO 3k is too much.

It’s a days work for a plumber and helper with about $650 in material.
You must be in an area where plumbers are cheap and plentiful. Having gas line work done here in NC ( and in MA where family lives) is very costly.

Earlier this year I had numerous quotes for a 22KW backup generator. The generator itself was around $6k. All in was between $14-$16k. So, about $9k to share for the plumbing/gas, electrical and mechanical work. Similar in MA, and in MI too.
 
You must be in an area where plumbers are cheap and plentiful. Having gas line work done here in NC ( and in MA where family lives) is very costly.

Earlier this year I had numerous quotes for a 22KW backup generator. The generator itself was around $6k. All in was between $14-$16k. So, about $9k to share for the plumbing/gas, electrical and mechanical work. Similar in MA, and in MI too.
I’m about 2 hrs east of the original poster. I have an idea of what things cost in New Orleans.

Running 80’ of gas pipe down a wall at ground level and connecting a generator shouldn’t cost 6k. Not in New Orleans in 2022.

I would consider doing it and driving over there for $3500k. I’d be done with the work in a couple hours. 🤣
 
When I’m really busy and I don’t have a relationship with the customer I often bid jobs very high.

It’s because I don’t really want the work. So I price myself out of the job.

Sometimes the person will pay the price…..That’s when that job becomes priority 🤣
 

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