Help? Buying a boiler this week and have a sizing question ?

antndrew78

Basically I have a Weil McLain eg 35 steam heating 8 Radiators that has always worked great but it leaked and is 26 years old so I need to replace by the end of the month I wanted to replace with the exact same boiler but I found a great deal on a new peg40 weil McLain brand new that a contractor has was wondering if this would be to oversized also the situation is this the previous owner removed all the insulation that was on the basement pipes including the header and the main line that runs the length of the basement just to heat the basement space so my thought would be that would compensate for the next size up please help any info would be great since heating season here in the north east is about to kick in

KC_Jones

You need to add up the EDR of all your radiators to know what size you need, without that information your question can't really be answered. That being said if the current one heats the house fine there is probably no need for anything bigger. Also for all you know the 35 is too big, without the EDR calculation no one can give you an intelligent answer.

If the 35 is the correct size I wouldn't take that 40 if it was free. Oversizing on any system costs you money in the long run. So while it may be cheaper now, it will cost you more to operate later. Pay me now or pay me later.

Also it wouldn't hurt to post some pictures of what you currently have to see how your current piping is. Are you doing the installation yourself?

antndrew78

No I am not a contractor will how do you size the radiators to get the edr and what is the abbreviation

Jamie Hall

The abbreviation is "Equivalent Direct Radiation"; the measurement is in square feet. It's basically the total surface area of the radiator. There are guides on this site as to the EDR of various radiator designs.

It really is critical to get the correct size...

You mention having taken the insulation off the mains to heat the basement. Put it back on. All of it. While having it off will put a little additional heat into the basement, not having it will affect the efficiency and proper operation of the whole system. There are better ways to heat a basement, if you need to.

KC_Jones

Start at the bottom of page 9 in this document, if you aren't sure what type of radiator you have post some pictures and measurements and we can help. Sizing is very important, don't size by the "best deal". Also don't have it installed by the "best deal". You want an installer that knows steam. Again post some pictures of your current install and we can help advise you on what you have.

Where are you located? We may know an excellent steam contractor in your area.

http://www.weil-mclain.com/sites/default/files/wm-boiler-replacement-guide.pdf

antndrew78

I did not remove the insulation it was done by the previous owner I am in Hawthorne Nj

KC_Jones

If you are in NJ there you need to call one of these 2 guys
@EzzyT
https://heatinghelp.com/find-a-contractor/detail/corrado-p-mastropaolo-inc

@Dave0176
https://heatinghelp.com/find-a-contractor/detail/dl-mechanical-llc

EzzyT

@antndrew78 send me a private message

Steamhead

KC_Jones said:

If you are in NJ there you need to call one of these 2 guys
@EzzyT
https://heatinghelp.com/find-a-contractor/detail/corrado-p-mastropaolo-inc

@Dave0176
https://heatinghelp.com/find-a-contractor/detail/dl-mechanical-llc

Agreed- these are two very good choices.

antndrew78

Thanks everyone I sent ezzt an email