Gas pipe sizing

[Hamberg]

Didn't want to step on the OP toes for the other thread going on but had (what is probably a stupid) question...

(also) looking into a whole house generator and wondering why you "would not" run the largest line possible? Example: my meter (250 CFH) is fed by 3/4" (no pressure rating on the (pre-meter) reducer) and the house is fed by 1" (have not measured the pressure there yet).

Question is, is there any reason not to tee off the 1" line and run 1" to the generator (approx 35' run)?

Question 2ish - one of the generators I'm looking at (24kw) has the following 1/2 and full load requirements:

Fuel Consumption @ 1/2 Load - NG cu. ft/hr 203
Fuel Consumption @ Full Load - NG cu. ft/hr 306

Based on the meter spec above is there a possibility we'd need to upgrade the meter? There are 30 other homes in the development with similar generators and I haven't seen any the had their meters upgraded

 

[Twowaxhack]

I would need to know the pressure or just size the line for 8”wc.

I can’t tell you if the meter needs upgrading because I don’t know what else is on gas

306,000 btu

 

[Twowaxhack]

A 1” line running 40’ at 8” water column will run approx 500,000 btu and that allows for 3”wc pressure loss.
3/4” would serve 216,000 btu.

You could run 1/2” if you had a 2# system

At 6” wc you’d need a 1.25” line

 

[Twowaxhack]

If you had the generator maxed out at 300k BTU’s and then fired a tankless off or a central heating system at 200k BTU’s the meter wouldn’t be able to handle the volume, or it would be maxed out…..

I’m reading that a 250k btu gas meter is good for excursions to 500k BTU’s.

I think I’d upgrade the meter……..

 

[Hamberg]

I'll get the BTU's but there are 2 (gas) HVAC units, a tankless WH, 50-gal DV WH, 5-burner cook top and something else I'm forgetting...

 

[Twowaxhack]

I'll get the BTU's but there are 2 (gas) HVAC units, a tankless WH, 50-gal DV WH, 5-burner cook top and something else I'm forgetting...

Yes, I say upgrade the meter