New furnace isn't giving off much heat

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New Grandaire furnace, gas high efficiency 40k btu in 1200 sft house near boston. All new insulated duct work, hooked up and seems to run right, but the air coming out of the supplies is only about 75 degrees. Any ideas why its so cool
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How many return registers do you have? Where is or are they?
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Maybe the blower turn-on temperature is set too low, or the high-limit temperature is set too low.
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wrote:

As far as i know, the newer ones w/ the circuit boards dont have adjustable high/low limits, No?
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One large one in the center of the house. The air volume is good
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Stupid question, but do you have the T-stat on "fan only", or in "cool" mode?
Can you feel heat or see the burners lit on the furnace?
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Heat only tstat, burners have a nice blue flame.
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How big was the unit you took out, 40k isnt much, is that 40k input or output. What did the installer that guarnteed it say.
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? It was an old hot water system but all the copper was stole out of the house
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Are you saying that this hot air system is totally new, with new ducts, etc, replacing an older hot water system???
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wrote:

Yes, Everything is brand new.
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What is the air temperature in the room? If it is comfortable, it does not matter what the air temperature leaving the furnace is. In fact, if it is too high you will get hot spots and temperature swings in the room. Longer blower on times and good circulation can add to your comfort.
I suggest you put the thermometer away for a few days and sit back and see how comfortable the room is and go from there. It may put our warmer air if the outdoor temperature goes down more too.
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It was about 60 inside. Took 90 minutes to raise the temp to 68 and thats with an outside temp of 55. I cant imagine this will be any better this February.
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Who installed it? An actual heating contractor? I'm asking because sometimes homeowners imagine themselves to be heating contractors and install furnaces themselves, often with humorous results.
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wrote:

Licensed hvac contractor. Union worker. Has always done good work for me. Hes never seen anything like this. Said hed get back to me tomorrow after he talks w/ some of the guys at work. Im just wonder if anyone else has experienced this.
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Licensed hvac contractor. Union worker. Has always done good work for me. Hes never seen anything like this. Said hed get back to me tomorrow after he talks w/ some of the guys at work. Im just wonder if anyone else has experienced this.
========= In none of the other guys at his place of business (which I assume is an HVAC outfit) say they've never heard of anything like this, you have a major problem.
Did this guy (or company) also sell you the furnace? This is different from my previous question.
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wrote:

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No, he called the order in to the local supply house and I picked everything up. Same as I always do for other projects. Usually I get whirlpool furnaces but this time they were out of stock and they gave me this grandaire.
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No, he called the order in to the local supply house and I picked everything up. Same as I always do for other projects. Usually I get whirlpool furnaces but this time they were out of stock and they gave me this grandaire.
=========
You usually get whirlpool furnaces? How often do you "get furnaces"?
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A couple of thoughts:
1. How close is the register you are measuring from the furnace? 75 seems cool but not necessarily from the register farthest from the furnace.
2. Do you have single or two stage system? Our two stage system only uses part of the burner capacity to maintain temperature in moderate conditions. If it has to work hard in cold weather, or to bring temp up after it has been reduced, second stage kicks in with more heat.
RonB
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73 degrees is furthest away 82 for one that is right off the plenum. Its a single stage
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