Rant of the day: Thermostats

[jasonl]

You know the little knob on the wall that makes the ac or heat come on (considering you have central ac/heat). Even vintage thermostats are nice. Honeywell still produces their "Round" series which is an age old design that works well. More and more homes are turning to the comforts of a digital thermostat, the better ones accurate to 1o.

Now here's where the rant comes in. Some people (other residents of this house), the same people that don't use ATC or hang up wet clothes, think that by lowering or raising the temp on the t-stat will speed up and slow down the system. They don't understand that a thermostat will MAINTAIN A TEMPERATURE. It's not a speed control. Once the room or house has reached a temperature the thermostat will turn off the air. I was smart enough to buy a Honeywell portable heater (with a digital thermostat) for these mornings when my dad refuses to start the heater or he plays with the thermostat and we either freeze or bake. No middle ground. What really makes me hot (pun intended) is at night when he turns it up to 74 or 75 and I am sweating in bed because I need to sleep snuggled under the covers. I CANNOT sleep on top of the covers. Then he fusses because one of us turns the ac on.

Every room should have it's own thermostat with a valve in the duct to block or direct air into the room. Yeah, it's called Zoning but it's very expensive. Like anyone from Opelousas would knw that. "You turn dat lil button and dat col' air comes out... BBrrrr... it's freezin chere"

 

[toggleswitch]

This is a big truth.
Thermostats, like most electric switches, are binary- 0 or 1, on and off. (Unless they are two-stage jobbies).

You may have to explain to the offender that the thermostat is NOT like a surface burner on the gas stove- with infinite heats. Set it and forget it- Thank you Ron Popeil.

Love the Honeywell rounds myself, but I have stooped to electronic thermostst in that the mercury in the aforementioned is HUGELY toxic to the environment.

 

[gregm]

steam heat and ......

I have the "old, gold, round Honeywell" and with steam heat, you only turn it up just enough to hear the furnace come on otherwise if you move the T-stat from 65 to 70 the house will end up 75 + . There is also an "anticipator" setting on the thermostat if you take the outer round cover, just below the dial is a copper colored pointer that you can slide left or right with a series of decimal point #'s ranging from .15 up to 1.2 As you increase, usually moving to the left towards 1.2 the boiler/furnace will cycle on and off LESS frequently. It should be set to whatever is on your "primary control" box for hot water systems; usually .2 or in older systems .4 THIS IS FOR OIL BURNERS, I don't know how it works for gas, but I assume its similar. For steam systems you multiply that # (.2 or .4) by 1.3 so that the boiler will run longer cycles to achieve an increased setting without going way above it and yet still maintain an existing setting without to much sway between degrees. Therefore the T-stat and boiler anticipate how long the furnace should cycle off and on to maintain and/or reach a set temp and not swing to many degrees above or below such set temp.

 

[toggleswitch]

I have old fired steam as well. Getting the heat-anticipator just right is a PITA.

Thank for the tips!

My system goes from 160*F to steam (212*F) in eight minutes, with the system fully pressurized in 13 minutes. (Hard-power down via 110v pressure-control hi-limit.) I moved it up to 5 psi, which is a bit high, but the burner now cycles less.

As you may know the only "problem" with steam heat is the over-shoot of the selected temp in mild weather, being spring and fall.

If I may suggest RIELLO brand burner heads for fuel-oil, (ditch your Beckett and Carlin ASAP, IMHO))the RIELLO burns VERY clean, meaning the boiler/furnace no longer needs a yearly cleaning. Balanced flue options are avaiable to use outside air for combustion, which prevents a negative pressure in the house (read: drafty house).

P.S. the fuel oil co. will give you a credit for your old burner- they cannibalize it for parts to make warranty and service-contract repairs.

http://www.riello-burners.com/2_products/2_oil-burners/3a_40-series-oil-fired.asp

 

[rayjay]

Thermostats

Greg, A lot of people do not know how these thermostats work. When we lived on rent in my aunts house (25+ years ago) that had oil steam heat, I noticed that the burner would keep cycling on and off till the temperature was reached. Now..I have a friend in heating and cooling which I have learned a lot from over the years. He told me also how to set the heat anticipator in the thermostat. Hot Water and Steam need to be set hi to keep the furnace running longer. It just took longer to heat the house when the boiler keep cycling on and off. The sad part about it is that the boilers (2 family house) have been their for years which my uncle had installed and have worked this way. I would think that the furnaces would draw more fuel by cycling off and on than by just staying on until the heat requirement was meet or the steam/hot water requirement was meet in the boiler. It is a shame that a lot of heat contractors just do the installation and slap the new thermostat on the wall without any adjustments! I have gas forced hot air in my house (which I HATE). I wish I could afford to convert to baseboard hot water heat (maybe some day). ARE YOU LISTENING STEVE?

Ray

 

[gregm]

thanks

wow, good info about RIELLO, I will def keep that in mind, I just replaced three somewhat major components on my burner, the primary control, the "igniter box", both right on top, side by side and the "tankless" for domestic hot water. I thought my boiler was newer because it is so small but I now realize it is just under 20 years old. If I am here another five to ten years, I may and will probably have to replace the entire boiler, but who knows. Steam systems rust out faster, because they are "open" unlike forced/gravity water systems which are "sealed". Then again, there are still many old boilers out there that can last a lifetime ...........

 

[frigilux]

Lord! Up here in the midwest, many people turn their thermostats down a few degrees at night, not up to 74 ot 75. That would drive me crazy, too.

 

[toggleswitch]

I was acutally able to run hot-water baseoard heat off my steam system to heat the basement. The hot-water loop is on the same level as the boiler.

Most circulators on hot-water systems push the return water thorugh the bottom of the boiler. Heated (non-potable) water comes off the top.

With my setup, it was necessary to have a circulator (that is suitable to open-systems) suck the water out of the lowest part of the boiler, push it through the loop and return it about a foot higher, which in my case is near the top of the boiler- but from the side.

It is necessary to do this because above a certain point there is no water; it is steam.

It is important to have an aquastat (water-temp sensing thermostat) maintiang a min. temp in the boiler, otherwise there will be no heat (in the basement) unless the main level's thermostat is calling for steam.

 

[toggleswitch]

Controlling this basement level heating is a classic Honeywell round (they are off-white now -wink-).

No "OFF" Position, no chance of weak batteries preventing heat from comng up and hopefully no chance of it failing as would the electronic one located on the main level.

When I am away in Florida in the winter, I am reasonably confident that with two zones, [one with no *OFF* position] the system won't shut off (or BE shut-off)and not deliver any heat. Can't have frozen pipes!

 

[petek]

I know exactly what Jason is saying because I live with one of those people that believes turning the Tstat up to "bake" will warm the house up faster, this same person also dials the dryer to the upper limits of "more dry". I've explained it over and over for years to no avail. It doesn't stop there either, whether in the car or truck it's the same thing, summer means the a/c dialed right down and in the winter slider right over to max heat, when you say it's getting too hot they slide it right back to the far reaches of the cool side, there's no middle ground.
Which reminds me when I get back home to moms to change her Tstat to one of the new Honeywell digital roundies. When she had her central a/c put in about 10 years ago they took out the old gold roundie and put in a cheap plastic Tstat with a lever on the side which you can never get exact and she's often said the roundie was so much easier. She doesn't want a fancy setback, too much fussing. But at least she knows she doesn't have to "crank it up" to warm or cool the house faster.

 

[DADoES]

I recall numerous times when working for the Whirlpool dealer in high school and helping on a refrigerator delivery, we'd set the controls to a normal position, and the customer would say something along the lines of "set to coldest so it'll cool down faster." Uhhhhh, no. Same for window units. I had a dialog in another forum several months ago with someone who complained how high is her electric bill with window units. She ran the 'stat at the coldest position and the fan on the lowest speed, thinking she was saving electricity 'cause it wasn't blowing so hard. duhhhhhh.

 

[toggleswitch]

What I want to know is how do people who have NO CONCEPT of how anything works (or is built) jump to such misguided conclusions.

Let's think aobut this logically. At 110 v, a window fan is 1 to 2 amps. Whereas a window rattler(window A/C) is 5 to 7.5 amps. What could the difference in the power draw be... the compressor maybe?

Is it not clear that the compressor is the main expense to run? Moving (or releasing) heat is the energy hog, not a dainty little fan.

DUH!!!!

 

[DADoES]

Car accelerator 100 MPH = lotsa gas
Car accelerator 20 MPH = little gas

Gas stove burner on high = lotsa gas
Gas stove burner on low = little gas

Window unit fan on high = lotsa electric
Window unit fan on low = little electric
(compressor pumping 24/7 = no reference)

 

[Cybrvanr]

The argument about the automobile gas pedal is that although you are burning more fuel, you will get there faster. The problem is that the person making this argument disregards some basic laws of physics. One of the most important being the law of inertia. It takes energy to make the vehicle change speed, so accellerating quickly off of lights and turns will consume more fuel getting the vehicle up to speed. There's also air and rolling resistance, which increases exponentally with speed!

NOW...about that air conditioner! Oddly enough, running the fan on a LOWER speed makes an air conditioner consume MORE power. Think I'm full of it? Well, if you've got a "watts up" or "Kill-a-watt" watt meter, try it for yourself! My 12,000 window unit in my attic consumes 1400 BTU's on high, and 1650 on low on a summer's day. I had an HVAC tech explain it to me when demonstrating a manifold gauge set connected up to a system. The problem is with less airflow over the coils, the head pressure in the condensing coil gets higher (less freon is condensing into liquid) Because the indoor fan is turning slower, less freon is being evaporated too. The result of this is that the compressor must work harder making higher pressures with less gaseous freon! He stated that LOW settings should only be used during nighttimes or when outdoor temperatures are low. This is because the lower outdoor temperatures allows more freon to be condensed, and the pressures will be lower anyways, and it won't make a difference. He was right, I tried my Watts-Up meter on the attic unit again, and I found the unit to pull about 1350 watts in high or low at midnight when it was 72 degrees outside!

I guess the thermostat thought that the setting will make the unit produce more power acutally comes from the automobile's HVAC thermostat, where moving the lever off the extreme settings will make the systemm cool or heat less. It's more of an analog device, where a household thermostat is a digital one. It could also be something that stems from the old days when adjusting dampers on the old coal systems would actually regulate the amount of heat the system produces.

 

[DADoES]

If I am not mistaken, a car a/c runs at full output at all times (when it's on). Adjusting the temperature simply bleeds some of the cooled air through the heater manifold to warm it back up. Same effect whether it's a manual adjustment lever or an auto-temp system. There is (typically) a thermostat that cycles the compressor to keep the evaporator from freezing-up, but it is not directly tied to the temp control (far as I know).

 

[southernmdgeguy]

Car A/C compressors

You are correct, A/C compressor in the car is either on or off, it cycles from both pressure and a temp sensor on the evaporator that keeps it from freezing up. The blend door between outside air, heated and cool air sets the output temp based on demand. I was going to add to the above thermostat talk by mentioning people with auto temp systems in their car that do the same, put it to 90 or max in the winter, instead of leaving at some sane temp like 72 and letting the expensive system they paid for do the work for them.. My sister in law is famous for this, both in summer and winter, puts it on max then complains that the fan is too loud so she shuts it down to minimum.. and it just makes me want to scream!

 

[petek]

re the car temp stat.. regardless if it doesn't make a hoot of difference gas wise, they're still idiots in my books LOL

 

[DADoES]

I let the auto-temp on my I30t do its thing. But I also switch it to Econ(omy) mode when conditions allow (although that doesn't really make much difference on MPG).

 

[jasonl]

I learned how to adjust a heat anticipator when I had an analog thermostat when I was living in my trailer. The heater would run until I was baked, so I nudged it a little lower every time until it felt right. Of course when I got a Honeywell Round digital it made the world of difference. If I ever buy another house with central AC, it's getting a Digital Round. THE best.

The guy that I work with is super computer tech smart but oddly enough, he didn't know how to program the thermostat in his/soon to be mine office. And he was one of those "it's hot in here, let's set it to 60" people. HELL NO. First of all, I programmed the T-stat to give us 72o of cool or 68o of heat from 8-5 on weekdays and set back on weekends and nights. Now I can leave it be and switch to heat if needed.

Window AC's don't have the best thermostats in them but the digital ones work ok. But after figuring out what my settings are according to comfort that's what I use. No up and down controlling, and HI fan all the time except for bedtime or early morning. I love window units because of the hum and the noise. Great to sleep to. The newer Window units automatically adjust the fan for you if needed. The Frigidaire Energy Star units will do that now.

But Thermostat Wars persist in the house. Me and my mom likes it cool at night while my dad loves to be warm. And if I even LOOK at the thermostat he'll pipe up and fuss. I'll be glad when I move out.