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hr(bob) [email protected] hr(bob) hofmann@att.net is offline
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Default thermostat setting

On Jan 5, 12:13*pm, ransley wrote:
On Jan 5, 11:24*am, wrote:





On Jan 5, 11:40 am, ransley wrote:


On Jan 5, 2:19 am, "James Sweet" wrote:


wrote in message


....


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.


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.- 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.- 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).