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[real bill]

Hope everyone's staying warm in this frigid weather.  I was just wondering if my heat exchanger is too small for zero degrees weather as it's a 125,000 btu heat exchanger.  It keeps up nicely in normal winter weather, but struggles in zero weather and the wind is blowing.  Any ideas?  My boiler is Global  Hydronics GL 2000 with 300 gallon water capacity.  I sure I have plenty of stove for heating 2000 square feet.

[hondaracer2oo4]

Does the exchanger fill up the entire plenum or is it smaller than the plenum? Also how is it plumbed? Does the water entering the exchanger enter the discharge side or the inlet side? What is your temp drop from inlet to outlet?

[Steinacher Sales]

I have a 125,000 btu house furnace.
My home is 1500 sq. ft.
I have the Shaver Pro Series 165.
The water temp. in the furnace is 165.
I heat my domestic water to 125.
The heat exchange that fit my plenum the best was 140,000 btu.
The air comes out my furnace ducts at 130 degrees.
Works well.

Greg Steinacher
618-401-0726
www.midwestoutdoorfurnace.com

[mlappin]

Hope everyone's staying warm in this frigid weather.  I was just wondering if my heat exchanger is too small for zero degrees weather as it's a 125,000 btu heat exchanger.  It keeps up nicely in normal winter weather, but struggles in zero weather and the wind is blowing.  Any ideas?  My boiler is Global  Hydronics GL 2000 with 300 gallon water capacity.  I sure I have plenty of stove for heating 2000 square feet.

Not sure about the new condensing furnaces, but when Dad and a friend were installing furnaces on the side the wholesaler told them ideally a furnace would be sized properly if at zero it ran constantly. If it doesn't run long enough then you tend to get warm and cool spots i the house as the air doesn't circulate properly.

[Jwood]

Hope everyone's staying warm in this frigid weather.  I was just wondering if my heat exchanger is too small for zero degrees weather as it's a 125,000 btu heat exchanger.  It keeps up nicely in normal winter weather, but struggles in zero weather and the wind is blowing.  Any ideas?  My boiler is Global  Hydronics GL 2000 with 300 gallon water capacity.  I sure I have plenty of stove for heating 2000 square feet.

Not sure about the new condensing furnaces, but when Dad and a friend were installing furnaces on the side the wholesaler told them ideally a furnace would be sized properly if at zero it ran constantly. If it doesn't run long enough then you tend to get warm and cool spots i the house as the air doesn't circulate properly.

You are correct mlappin

[mlappin]

One other thing, if the wind affects how well your heat exchanger can heat the house, might be time to take a close look at your windows and siding. New double pane windows in just the south and west side of the house made a world of difference, adding fanfold, house wrap and new siding really cut down on the wood usage. Soon as I can get the last of the peg and post out of the attics I plan on blowing in at least another foot of fiberglass.

[Jwood]

Also look at how they rate the heat exchanger because most of them base it off 180 degree water at somewhere around 12 gpm I believe so if you are not pushing that much volume you are not getting the full rating of the heat exchanger.

[mlappin]

Also look at how they rate the heat exchanger because most of them base it off 180 degree water at somewhere around 12 gpm I believe so if you are not pushing that much volume you are not getting the full rating of the heat exchanger.

[U.P. Doug]

Is your blower fan on the higher setting? I have a Trane condensing furnace and looked up the manual on line and found there is a jumper wire that I can add to increase the air flow to high all the time. My house is not large, around 1700 sq. ft. and my furnace is 60,000 btu propane. With the boiler set at 172 on, and 182 off, with the jumper wire in place, I have had no issues heating the house when we were -39 here for a few days.

[willieG]

UP Doug brings up the first thing to check...when the furnace blower is running and the house is calling for heat feel (or check) the temps on the inlet and outlet of the heat exchanger. if they are close together you should look at speeding up the fan. also make sure your plenum (or where ever you have the heat exchanger installed) there is no way any air can get around it. if there is a gap around it then air will flow around the exchanger and you will not be getting the full benefit of it (again the temp differences will be close)

[U.P. Doug]

Based on the good info I got on this site, I installed temp gages on the copper line just before it enters the water to air exchanger, and one where it comes out. After setting the furnace fan to high I noticed I was getting a higher temp. loss so I kicked the pump up to medium speed and it is working great.