Question on HX btu output

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ryooper

New Member
Dec 18, 2013
49
centralu.p.
Hi all I m looking at getting a Eko 40 my current system is water to air hx witch has a 120,000 btu output with the 40 being a higher output than that would I need to get a bigger hx. Any feed back would be much appreciated. Thanx In advance.
 
Ok let me revise my question I know its a stupid one. I guess what I would like to know is if I have storage min of 500 gal. how many btu s are in that forgive me for I am not a heating expert but thank goodness for the boilerroom. I mean how is that transferred can I throttle that back somehow? I also have 3 cast iron rads I would like to plumb in to my system if any more info is needed let me know sorry its a busy time right now, just tryn to get the ball rollin on the new heating system. would like to have everything ready to start install by May. Thanx again.
 
What is the minimum water temperature you can heat your air system effectively with?

Say you can heat your house when you have 140 degree water and you charge the tank to 190 degrees. That's a 50 degree difference
BTU in the tank = 50 degrees * 500 gallons * 8.3 lbs per gallon = 207500
 
You will get more response with more details about your situation.

I would suggest searching and reading about Forced air heat exchangers.

Short answer is no, you don't need a larger exchanger to accommodate the EKO. But how many btu per hour do you need to heat your home?

To some extent oversized heat exchangers might let you use cooler water temps from storage to still get heat.

My heat loss at -15 is 45,000btu/hr. I have a 115,000 btu exchanger. I can heat with 130 degree water but prefer not to go below 140.

Use this to calculate available storage btu's.

(btu's to raise/lower 1 gal of water 1 degree) X (degree change) X (gallons)

8.33 X 45 X 500 = 187,425 btus

gg
 
What is the minimum water temperature you can heat your air system effectively with?

Say you can heat your house when you have 140 degree water and you charge the tank to 190 degrees. That's a 50 degree difference
BTU in the tank = 50 degrees * 500 gallons * 8.3 lbs per gallon = 207500
Yes 140 is about the min after that the blower is running constantly to keep house at set thermostat temp.
 
You will get more response with more details about your situation.

I would suggest searching and reading about Forced air heat exchangers.

Short answer is no, you don't need a larger exchanger to accommodate the EKO. But how many btu per hour do you need to heat your home?

To some extent oversized heat exchangers might let you use cooler water temps from storage to still get heat.

My heat loss at -15 is 45,000btu/hr. I have a 115,000 btu exchanger. I can heat with 130 degree water but prefer not to go below 140.

Use this to calculate available storage btu's.

(btu's to raise/lower 1 gal of water 1 degree) X (degree change) X (gallons)

8.33 X 45 X 500 = 187,425 btus

gg
I did the heat loss calc and came up with 55,000 btu/hr I'm heating 2,800 sq. ft. does that sound right house was built in 83
has newer windows and added ins. still have some more tightening up to do.
 
55k btu per hour in 2800 sq ft is doing pretty well in this climate. My 2400 sq ft average 1991 house in the eastern UP has a design loss of about 60k btu per hour. I used -20F as the outdoor design temperature. We had four or five nights that were colder than that this year.
 
55k btu per hour in 2800 sq ft is doing pretty well in this climate. My 2400 sq ft average 1991 house in the eastern UP has a design loss of about 60k btu per hour. I used -20F as the outdoor design temperature. We had four or five nights that were colder than that this year.
I may have been a little too generous with some of the R values so it may be a little higher I had mine at -20 also.
 
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