Confused：自住房FURNACE REPLACEMENT 更新

找了两个公司：

A 说要96% 100，000BTU KENMORE 2-STAGE 4，200 （可再要约300 UTILITY REBATE）

B 说要96% 70，000BTU LENNOX 2-STAGE 3，340 AFTER ALL REBATES

问题：自住房 2层楼，CRAWL SPACE，2300 SF。到底要多少BTU？

1）网上有的说52，000， 如下（加了ZIP）

Choosing Furnace Size: Measuring BTU

Top of Form

Sizing Estimator for Furnaces

Square Footage:

Home (Excluding Basement)

Room(s)

Desired Indoor Heating Temperature (F):

Stories:      1 2 Tri-level

Zip Code in USA:

Insulation Level:      Basic Above Average Outstanding

Basement:    Yes No

Estimate

Results:For your 2300 square foot home in ***you will need a Heating Unit with 52,000Output/Effective BTUs.

 

Bottom of Form

 

2）有的说 12000 btu per ton and a ton is equal to 600-800 sqft/per ton depending on the year of the house (insulation windows age things like that) If your house is old with poorly insulated windows and poorly insulated we would use 600....So 2300 sq ft divided by 600 =3.8 ton house unit need to heat. 3.8 ton x 12000 btu needed to heat the house =45600 btu output of heat. Since were using extreme old equipment and poorly insulation & poorly insulated windows this will be the worst case scenario. Your heating unit is only (which I doubt its this bad) a 70% Efficient heating unit. So at 70% efficient unit to have a output of 45600 BTU it input BTU would have to be around 65000 BTU.

MY CASE：2，300/600*12，000=45600/。96=47，500

3）有的说

Simply multiply the appropriate factor below in the chart and by your zone from the map by your home's total heated square footage to arrive at your required heating output. 

For example, if you live in the yellow zone, your home is well insulated, and you have 2300 heated square feet:
Zone 3/4= 45 Btu’s per square foot (from the chart below)

2300 X 45=103，500

Confused!

请帮忙！

原贴；大雪天得换Furnace怎么选

 

Furnance blower 坏了。目前换要价600多。天太冷（-10F)，只好认了。过一阵准备换个新的。
自住房，1988年的炉。75，000BTU
问题：
1。是找HOMEDEPOT要个FREEESTIMATE 还是找HEATING A/C 公司？
2。价钱如何？ 看HOMEDEPOT $1，000-2，000， 
http://www.homedepot.com/b/Heating-Venting-Cooling-Heaters-Forced-Air-Furnaces/60000-90000/N-5yc1vZc4lkZ2bctniZ2bctpiZ2bctpjZ1z10n1h?NCNI-5
80,000 95%should be ok?
那INSTALLATION 怎么算？
3.要注意什么问题？
先谢了！

 

所有跟帖： 

• Well if your old 75k has been sufficient then the new 96% 75k sh -borisg- ♀ (150 bytes) () 01/13/2014 postreply 12:49:14

• 90年代以前的furnace 的热效率一般低于70% -big-guy- ♂ (122 bytes) () 01/13/2014 postreply 16:43:47