Gas and Oil Home Heating Furnaces - Proper Size Furnace???
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01-23-01, 10:03 AM
Hi All,
I recently purchased a new construction house with about 4200 sq. ft. living space. Now that winter is here, we can't seem to warm the second floor rooms. The basement has about 600 sq. of finshed area with 4 vents. We've tried closing them but the house actually seems warmer (but not too much) than with them closed. Keeping doors closed only makes the rooms colder. The windows are standard for new construction but I would expect the first floor to be just as cold as the second which it is not. We have a Rheem Criterion furnace Model # RGPJ-10EBRJR 100,000 BTU unit and still wonder if this size is actually large enough for the house? Any help would be greatly appreciated and warmly received.
Ron
I recently purchased a new construction house with about 4200 sq. ft. living space. Now that winter is here, we can't seem to warm the second floor rooms. The basement has about 600 sq. of finshed area with 4 vents. We've tried closing them but the house actually seems warmer (but not too much) than with them closed. Keeping doors closed only makes the rooms colder. The windows are standard for new construction but I would expect the first floor to be just as cold as the second which it is not. We have a Rheem Criterion furnace Model # RGPJ-10EBRJR 100,000 BTU unit and still wonder if this size is actually large enough for the house? Any help would be greatly appreciated and warmly received.
Ron
PDF
01-23-01, 03:24 PM
Make sure you have good air supply thru all vents.During construction a supply vent connector or part of return in attic could be not sealed correctly.Need to know area you live in.Other homes in your area with same problem?Remember you ARE NOT getting 100,000 btus,especially if your unit is rated at 80% efficiency.PDF
fjrachel
01-23-01, 08:05 PM
At 4200sq.ft.!!!!!100,000btu furnace!!!! No way you have only one system in that house. I'll bet you got another unit in the attic for the second floor..If you don't, you'd better have your builder have one put in. If you live in the southern states it will more than likely be a heat pump.
01-24-01, 04:57 AM
Thanks for replying. I live in New Jersey. The house next to me also appears to be having a similar problem in not being able to warm the house without setting the 'stat to 80 degrees or MORE. Sounds like the unit isn't big enough. that would make alot of sense. Should I give Rheem a call and see what they say???
Ron
Ron
fjrachel
01-24-01, 03:14 PM
I'm in NJ myself. Most homes that are as large as yours have two systems. Sometimes there's one in the attic and sometimes both are in the basement. Seems to me you would have to have two systems, for the a/c also. Someone messed up.
01-25-01, 10:00 AM
The heating people are coming out today but our past experiences with them have not been too good. they will probably say there's nothing wrong. Just from what I can see, there seems to be very little air flow coming out of the second floor vents. First floor has good flow but t's not very hot. I read somewhere that the air coming out of the vents should be pretty warm, between 98 and 138 degrees. Is that right????? fjrachel, since you are a tech, is there any special way I should deal with my heating people? I tried being nice and understanding to there heavy schedule, even accomodating to there needs.
Thanks Again,
Ron
Thanks Again,
Ron
lynn comstock
01-25-01, 11:02 AM
1) Airflow is the key to solving your problem. Using 2 systems to solve heating or cooling problems is a common way to get around the ignorance of proper duct design.
2) The most common complaint of multi-story homes would be OVERHEATING of the higher floors since some of the lower floor heat rises to the ceiling and slides up the stairwells to add heat to the upper floors. (Since this isn't happening and the 2nd floor is too cold, Your duct sistem is REALLY delivering inadequate heat (WARM AIR) to the 2nd floor)
3) Choking the airflow to the 1st floor rooms will tend to increase the air to the upper floor.
4) If the friction of the additional ducts and fittings that serve the 2nd floor is significantly more than the first floor, the adjustments in part 3) may have little effect.
5) The contractor will likely tell you that the furnace is big enough and that there is nothing wrong with the furnace. Chances are that this will be TRUE.
6) The problem is that the heat DISTRIBUTION system (ductwork) is not dividing the heat correctly to match the needs of each room. Proper design begins with a room-by-room heat load calculation. Then the ductwork can be designed to deliver the correct share of heated air to each room.
7) Where to go from here: Air DISTRIBUTION is what you should focus on with your contractor. If they stall you long enough, you will lose the opportunity to get a remedy under warranty. Some states have a "Registrar of Contractors" to enforce workmanship and qualifications. Depending on the construction details and space available, a repair may be very difficult and expensive. Be insistent or you may be stuck with what you have or a huge bill to solve the problem.
Good Luck
[Edited by lynn comstock on 01-25-01 at 08:16]
2) The most common complaint of multi-story homes would be OVERHEATING of the higher floors since some of the lower floor heat rises to the ceiling and slides up the stairwells to add heat to the upper floors. (Since this isn't happening and the 2nd floor is too cold, Your duct sistem is REALLY delivering inadequate heat (WARM AIR) to the 2nd floor)
3) Choking the airflow to the 1st floor rooms will tend to increase the air to the upper floor.
4) If the friction of the additional ducts and fittings that serve the 2nd floor is significantly more than the first floor, the adjustments in part 3) may have little effect.
5) The contractor will likely tell you that the furnace is big enough and that there is nothing wrong with the furnace. Chances are that this will be TRUE.
6) The problem is that the heat DISTRIBUTION system (ductwork) is not dividing the heat correctly to match the needs of each room. Proper design begins with a room-by-room heat load calculation. Then the ductwork can be designed to deliver the correct share of heated air to each room.
7) Where to go from here: Air DISTRIBUTION is what you should focus on with your contractor. If they stall you long enough, you will lose the opportunity to get a remedy under warranty. Some states have a "Registrar of Contractors" to enforce workmanship and qualifications. Depending on the construction details and space available, a repair may be very difficult and expensive. Be insistent or you may be stuck with what you have or a huge bill to solve the problem.
Good Luck
[Edited by lynn comstock on 01-25-01 at 08:16]