Converting from a compression tank to a diaphram type

t_roy

I have a old Burnham Jubilee(oil fired)Specs are ; Valve capacity (min) lb per hr.-100 Net IBR ratings-Water-MBH.- 75. Paired with a 15 gal compression water tank. I would like to convert over to a baffled type tank. Do I base my btu from the 100 or the net of 75mbh?
I also removed 1-1/2, 1-1/4 trunk lines and replaced them with 3/4 hepex tied to cast iron radiators. I have read the post on compression tanks, however I am still alittle confused on basing a expansion tank on btu's or capacity of water. Estimating on a heating sq ft of up to 1500.

hot_rod

Link to a sizer program
http://www.amtrol.com/support/sizing.html

HVACNUT

Your converting to an air elimination system. You can't JUST install a diaphragm type tank. Your going to have to pipe in an air scoop with an air vent, or a Spirovent type.
Lipstick on a pig IMO.
What's your reason for converting?

t_roy

Yes, your right about the air elimination. Reason for converting is remod on the basement. Also thinking ahead if I need to replace the boiler.
Funny, your comment on lipstick on a pig. That's been said about my house. Lol.

HVACNUT

I would think hard about replacing the Jubilee before, or part of the basement renovation. That baby probably has to be split to get it out, and it won't be pretty.
If your enclosing the boiler room, make sure it has sufficient combustion air.