thermostat setting

[[email protected]]

My thermostat runs my furnace about once every hour when it is 20
degrees and I am thinking about adjusting the swing on the thermostat
to a lower number so that the system keeps a more consistent temp. Is
this going to cost me more in gas. The swing will allow the system
(set at 62 for heat) to come on at 61 and run it up to 63. So the
swing is 3 degrees. I figure I might go to 2 or one to cycle the
system more and be more consistent temp. Any thoughts?

 

[[email protected]]

My thermostat runs my furnace about once every hour when it is 20
degrees and I am thinking about adjusting the swing on the thermostat
to a lower number so that the system keeps a more consistent temp. Is
this going to cost me more in gas. The swing will allow the system
(set at 62 for heat) to come on at 61 and run it up to 63. So the
swing is 3 degrees. I figure I might go to 2 or one to cycle the
system more and be more consistent temp. Any thoughts?

correction, the current swing is 0

 

[James Sweet]

My thermostat runs my furnace about once every hour when it is 20
degrees and I am thinking about adjusting the swing on the thermostat
to a lower number so that the system keeps a more consistent temp. Is
this going to cost me more in gas. The swing will allow the system
(set at 62 for heat) to come on at 61 and run it up to 63. So the
swing is 3 degrees. I figure I might go to 2 or one to cycle the
system more and be more consistent temp. Any thoughts?

Give it a try and see what happens. It sounds like your furnace is oversized
though, ideally on the coldest days you ever see, it should run nearly
constantly to maintain the desired temperature, though 61F is much colder
than usual, I would size it to maintain 70 so you have a bit of margin.

 

[ransley]

Give it a try and see what happens. It sounds like your furnace is oversized
though, ideally on the coldest days you ever see, it should run nearly
constantly to maintain the desired temperature, though 61F is much colder
than usual, I would size it to maintain 70 so you have a bit of margin.

It might take 5 minutes for the furnace to get to full efficency,
running once per hour is not much 61f and a 3f swing for me is
uncomfortable, 10 minute running cycles are short but I dought you
will notice a difference narrowing the cycle

 

[[email protected]]

It might take 5 minutes for the furnace to get to full efficency,
running once per hour is not much 61f and a 3f swing for me is
uncomfortable, 10 minute running cycles are short but I dought you
will notice a difference narrowing the cycle

the cycle runs about 12 mins. and yes the furnace is too large by
about 30,000 btu. Not installed when I was living here. Wil there be
a diff in usage of gas though. I can go to lower setting on this
thermostat, even though there is 0 swing right now. When I checked it
said 0 swing at 63. Went to -1 and it dropped to 62. So I assume
that will keep it right on the mark of 62? Obviously dont want to go
lower than the set temp though.

 

[Glenn]

I like even heat and cooling. I have an up to date
thermostat that can be set to 0.2 of a degree. The
heat comes on often that way but I waste not one BTU of
heat because I run the fan 24/7. Having it set that
way with auto fan will waste some heat because the
plenum has to pre-heat before the blower comes on. Not
a lot of waste but some.

 

[ransley]

the cycle runs about 12 mins.  and yes the furnace is too large by
about 30,000 btu.  Not installed when I was living here.  Wil there be
a diff in usage of gas though.  I can go to lower setting on this
thermostat, even though there is 0 swing right now.  When I checked it
said 0 swing at 63.  Went to -1 and it dropped to 62.  So I assume
that will keep it right on the mark of 62?  Obviously dont want to go
lower than the set temp though.- Hide quoted text -

- Show quoted text -

What I did was actualy cut gas to the furnace to lower btu input, I
just turned down on the supply valve as it was running so I could see
the flame and had a thermometer inserted just above the heat
exchanger, I just cut it maybe 10-15f it evened heat and lowered
output. If you have a dual stage setup be sure its running on low
stage.

 

[hr(bob) [email protected]]

What I did was actualy cut gas to the furnace to lower btu input, I
just turned down on the supply valve as it was running so I could see
the flame and had a thermometer inserted just above the heat
exchanger, I just cut it maybe 10-15f it evened heat and lowered
output. If you have a dual stage setup be sure its running on low
stage.- Hide quoted text -

- Show quoted text -

I measured the diameter of the gas nozzle in my furnace, it agreed
with the BTU rating, then I filled in the nozzle and redrilled it out
at a smaller diameter - about 80% of the original gas flow. So now I
have a smaller flame and the furnace runs longer, but the gas
consumption is definitely down based on BTU's burned per degree days.
I also run my furnace blower continually when the temps are below
about 20F to keep the various parts of my 4-level split-level home
more evenly heated. I do pay some in electricity for comfort, but
that's what we have furnaces and electricity for (to dangle a
preposition).

 

[CJT]

I like even heat and cooling. I have an up to date thermostat that can
be set to 0.2 of a degree. The heat comes on often that way but I waste
not one BTU of heat because I run the fan 24/7. Having it set that way
with auto fan will waste some heat because the plenum has to pre-heat
before the blower comes on. Not a lot of waste but some.

Running the fan 24/7 costs money, too.

 

[CJT]

It might take 5 minutes for the furnace to get to full efficency,
running once per hour is not much 61f and a 3f swing for me is
uncomfortable,

It must be torture for you to leave the house. What are you, the
princess who could feel the pea through 20 mattresses?

10 minute running cycles are short but I dought you

 

[CJT]

What I did was actualy cut gas to the furnace to lower btu input, I
just turned down on the supply valve as it was running so I could see
the flame and had a thermometer inserted just above the heat
exchanger, I just cut it maybe 10-15f it evened heat and lowered
output. If you have a dual stage setup be sure its running on low
stage.

I hope you checked the flue temperatures before and after, and have
a good CO monitor.

 

[Glenn]

Running the fan 24/7 costs money, too.

Most electricians say the difference in the starting
windings usage and running 24/7 about balance out so
why not be comfy.

 

[Ralph Mowery]

I like even heat and cooling. I have an up to date thermostat that can be
set to 0.2 of a degree. The heat comes on often that way but I waste not
one BTU of heat because I run the fan 24/7. Having it set that way with
auto fan will waste some heat because the plenum has to pre-heat before the
blower comes on. Not a lot of waste but some.

What you need is the newer varitable speed fans. They come on when the heat
comes on and run at a slow speed. As you heat up, the fan speeds up.

 

[CJT]

Most electricians say the difference in the starting windings usage and
running 24/7 about balance out so why not be comfy.

I doubt "most electricians" say that, and if they do, they're wrong.

 

[Glenn]

I doubt "most electricians" say that, and if they do,
they're wrong.

--

Whatever. Certainly not worth arguing over [g]