gas heating chimney sizing using b-vent

Paul S_3

Hey everyone I have this job where I'm relocating a boiler room...I will be installing 4 natural draft 70k btu input hot water boilers with 4 40 gallon water heaters.....the old boiler room setup had a masonry chimney that is falling apart. ....this job is in NYC ....I'm using the nyc gas fuel code to size the chimney. ...I came up with 10 inch b vent. ...With all the appliances I get 440 k btu....the height of the chimney will be around 40 feet. ...no lateral connections. ...I used a connector rise of 3 feet.....I used the chart for 2 or more appliances, category 1,appliance vent connection=single wall metal connector. I used the chart on page 71 of the NYC gas fuel code. I myself have never done this before. ....just want to double check my sizing of 10 inch b vent with you guys thank you much appreciated Paul S

Paul S_3

?

ChrisJ

I'm not a pro but as long as you're using a chart provided by the manufacturer of the b-vent, and using the "multiple appliance" table you should be fine.

If I was you I'd call the manufacturer and just double check with them. Whether or not NYC code has something different I have no idea.

But, worse case, I figure by posting I'll at least get your thread back to the top of the list.

Tim McElwain

I do not have my code book handy let me get hold of it and check and get back to you.

Paul S_3

Thank you Tim

Tim McElwain

Your calculations are correct in accordance with NFPA 54 National Fuel Gas Code.

I would suggest however that you refer to Selkirk Metalbestos handbook for correct set up and application. If you do not have a copy I can send you one just contact me at my e-mail address gastc@cox.net and give me your address and I will mail it to you.

Tim McElwain

Handbook is in the mail.

ChrisJ

Tim McElwain said:

Handbook is in the mail.

You're one of the best Tim.

Tim McElwain

Thank you!