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boden

Red Green wrote:
BobK207 wrote in news:a56a44ef-7e6f-4a42-babd-
:

On Jan 23, 4:38 pm, John Smith wrote:

I have a 2,000 sqft house. I suspect the heating system (Trane) is
not working properly because it takes one hour to raise the
temperature four degrees.

The service man from the company which installed the unit last
summer told me the system works fine. He said the supply air is
105 degree and return air is 71 degree and usually he only gets
101 degree for supply air.

I don't have much experience with gas heat and wonder if a supply
air of 105 degree is normal. Any thoughts?

John-

Sounds about right...as everyone has posted.

You want a system that can just barely keep up on the coldest day in
its design life.

Sounds about right...for AC on the warmest day.

I've done some heating experiments in a couple homes and 4 degrees per
hour is about in the middle of the performance I've measured.

When I allow my house to "soak" for a weekend away & the outside temp
is in the low 50's, high 40's the house settles near 50..... brrrrr!

My home heats at about 6 deg per hour...... approx 1 deg rise in 10
minutes. I have run this experiment a couple times.

During "normal" duty it runs about 10 minutes on, 20 minutes off.

When its really cold outside (well, cold for SoCal, low 30's). The
gas furnace runs nearly constantly to keep the house at 62 over night)

cheers
Bob

In addition to knowing the air temperature out of the furnace you need
to know how much air is flowing. It doesn't matter what the air
temperature is if there isn't enough mass flowing; the heating will be
insufficient. Also, since the measurements you have were obtained during
the summer, you may have heat loss due to poor duct placement and/or
lack of insulation. Measure the air temperature into the living space
at several locations and coming from the furnace (at the furnace) to
assess this.

Boden