想取代现有的古董3管fin radiators in my old house but I’m not sure how many BTU’s per foot they produce.
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Attachment shows 2 tube, 3 tube, and 4 tube (I’m not even sure what this style is called). I have the 3 tube arrangement throughout the house and I would like to be confident that when I upgrade, I’m getting more heat for each room in this 1650, modestly insulated, house.
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James,
If you take off the cover and examine one of these radiators, do you see any marks to give you a clue? Perhaps a manufacturer's name?
Those are the innards of cabinet type convectors. As shown in the picture they are rotated 90 degrees from how they sit in the enclosures.
If you measure the height & widths of the fins, and count the number of fins, and measure height & width of the enclosure they were in you can probably find a spec on a similar convector product. eg:
http://www.modinehvac.com/web/products/commercial-hydronic-equipment/convectors.htm
http://www.modinehvac.com/web/file?uuid=7ca61f5e-5554-4379-be2c-594b981a4614&owner=b7c1a0f1-c044-4ee5-aa41-9587d4a229d0&contentid=4026&name=AIR13-111.3_Convectors%2C_Technical_Manual.pdf
They are often specified for 215F steam and 200F entering water temperature (EWT), but the output can be inferred at other water temps:
At 180F EWT the output is about 80% of what it is at 200F EWT...
...at 140F EWT it's about 40% of the 200F EWT output spec...
... at 125F EWT (a good condensing boiler temp) it's about 25% of what it puts out with 200F EWT