gas pipe sizing?
We're thinking of adding a gas dryer and upgrading the kitchen gas cook top to a free standing stove.
My question is whether we have large enough piping for the demand - I'd like to get an idea before I have a plumber bid the job.
The service is natural gas. From the meter to the connection point of all the appliance feed lines is 20' of 3/4" black pipe.
We currently have: 40 gln water heater, 2 forced air furnaces, gas cook top, gas bar-b-que.
We'd like to add a gas dryer and replace the cook top with a free standing stove. My rough calc from on line tables is our total demand would be 386 CFH.
From what I read of on line tables our pipe would be undersized for that demand. Does practice allow any down rating of the demand (assuming not all appliances will be running at once)?