Newfangled home thermostat

[peter]

As most of you know, I'm in the HVAC industry. We do commercial and industrial work mostly. Anyhow, I've never been a fan of programmable t-stats. Whenever we'd install one in a restaurant (we do lotsa work in the food-service sector), we'd invariably get a call from the manager/operator on a Saturday night complaining that he/she/it couldn't adjust the temperature properly. Or, worst still, the dumbass got into the programming parameters and screwed it all up. I have hated programmable thermostats ever since. They're complicated to program, and way too easy to screw up.
Until now.



The new Honeywell Vision series. Mine's a VisionPRO because it's got a few control features you don't necessarily have in the Vision series. But the principal is the same, nonetheless.






It's touchscreen operated and it's amazing. You can program it to be dimly lit at all times and brighten up when you touch it...








One of my favorite features is that it has a built-in humidity control. With frost control, no less.






What does that mean? Well, I can program the humidistat portion of the thermostat to reduce the humidity setting based on the outdoor temps. While it's only logical that you would want to maintain an ideal 35-40% humidity during the winter months, doing so causes a major problem. Namely, condensation.
I've had my patio door literally freeze up on me because I insisted on keeping the humidity levels at around 40% when outdoor temps got down to around -12*C ( around +10*F) or lower. The colder it is outside, the more of a temperature difference there is between the inside and outside. So what happens? It's sorta like a cold glass of water on a hot summer's day. The glass sweats. Well, that's what happens to home windows when faced with colder outdoor temps. As energy-efficient as windows have become in the last decade or so, a window will never be as efficient as an insulated wall.
So this newfangled t-stat has what's called frost control. When connected to an outdoor temperature sensor (about $25), it will automatically roll back the humidity setting by a certain amount, based on settings from 1-10. You can control what amount. A frost control of 1 means you really don't want to see any condensation whatsoever, at the risk of having a much drier home. A setting of 10 means you want a more comfortable humidity level at the risk of seeing more/alot of condensation. For you southerners to be able to understand, it gets so cold out up here in Canada that you literally have to fight to open the patio door. Really fight. While the dog crosses it's legs and whines while waiting 'cause she has to go pee.....

[peter]

This is a pic of my HVAC system downstairs. The t-stat upstairs is connected to the vertical beige box by only 3 #18 wires. You would typically need at least 10-12 wires to be able to control what I'm controlling with only 3. The Vision t-stat needs as many wires as a typical thermostat as well. Obnly the VisionPRO uses a separate control panel, therefore reducing the amount of conductors needed. This can be handy for some people who cannot replace the existing 3 cond. control cable with a 10 conductor necessary for multiple stages of heat plus other control needs.

[SafariRob]

Nice looking thermostat, Peter. You've certainly put a lot of thought into your house's heating and cooling system. I must admit that I'm envious of your HVAC kung fu...must be nice! I could've saved myself time and money if I had known what I was doing when I started my radiant floor project.

By the way, here's what us south of the border po' folk use for a thermostat:


The world would certainly be a poorer place if not for the round face Honeywell thermostat...lol.

[e7ats]

OK, Now your just showing off.




I like it.

[Rileysowner]

I must say that would be nice. Alas, our furnace is so limited in what it can do, a thermostat like that would be a waste.

[crash]

we got a programmable about a month ago and it's been fantastic. installed it the same day that our new windows were put in. the combination of the two means a MUCH more consistant and lower temp setting. mind you it's not a fancy touch screen like peters, it has old school things on it called buttons. LOL

it was nice to toss the old slider and was super simple to hook up once the 2 wire was pulled and some new 4 wire was run.

i think we might even be getting central air in the spring. woo hoo .. adios window shakers.

edit based on peters note below: on my tossing comment, it was 'tossed' to a furnace installer for proper disposal

[peter]

Regardless of which brand/model of t-stat you have, if it's an electronic version it'll be 100% more accurate than the older electromechanical types. With tthe one I posted here, it seems to be even more accurate simply because I can ask for temps in .5 degree increments. Might no=t seem like alot, but after alot of experimentation we found that 22.5* was the most comfy, whereas 22* was very slightly on the chilly side. I never would have believed that .5 degrees woulda made any difference, but...
Also, the newer t-stats have an adjustment for how many CPH or cycles-per-hour you permit it to make. A cycle is an on/off event. So, if you allow it to make more on/off cycles, there's less chance of temperature swing. Which is what causes the "too-hot, then too-cold" feeling. Caution though, those with heat pumps beware. Having your compressor kick on too many times will shorten its life considerably. I wouldn't wanna see a heat pump compressor kick in more than mebbe 2-3 per hour, personally.

As an aside, remember to drain the mercury from your old t-stat into a glass vial and bring the vial to your local scrap yard for recycling. Mercury is very toxic and shouldn't be chucked into the garbage. We have about 6 fluid ounces accumulated at the shop so far, the bloody thing must weigh at least 1-2 lbs...

[BLAZER]

It's just amazing that you post that out here thinking anyone will care....
Just kidding, I know what you mean abouthtose pain inthe rear programmable ones. We have one at work and not even our maintenance guys can get it right, we either freeze or sweat our kahunas off. Doen't help that the AC side of things is completely hot so we get no air and the heat is screwed up as well. I have a cheapy on/off /adjust temp/ heat-AC-off digital that works just peachy!

[CaptSquid]

Meanwhile, I have an analog t-stat that isn't even close to being remotely near some kind of accuracy. If I set it at 72, it registers higher and I end up freezing my tochis. Plus, the furnace is pure convection. And there ain't no duct work to the bedroom.

[peter]

For those who still have electro-mechanical t-stats, here's a tip on how to help smooth out the temp swings. If you pull off the cover of any such stat, you'll find an anticipator adjustment. The range is usually .1 to 1.2 amps.
If you find that the furnace never stays on long enuf (kicks off too soon) unless you raise the temp setting, then your anticipator is set too low. If it's at .2 for example, raise it up to .4 or .5 and then let a day go by so you can see if the adjustment is ok.
If the opposite is true and the furnace doesn't seem to wanna kick off quick enuf, then reduce the setting instead.

The proper way to set the anticipator is to measure the amperage thru W, which is the wire that sends a 24v signal to your furnace. For those who have a simple 2-wire (2 wires to the t-stat) heating only furnace, measuring the amperage on either of the 2 wires is could enuf. For those with heating/cooling central systems, you need to measure the amperage thru W, then set your anticipator to that exact reading. For those with 2 stages of heating, measure the amperage for W1, set anticipator #1, then do the same for W2. NOTE: W1 needs to be calling for heat before measuring amp draw on W2.
You'd be amazed how much more comfy you'll be afterwards. Hardly any techs ever bother to check this adjustment, yet it's a crucial check.

Next week, we discuss personal hygiene and the pros/cons of using hypoallergenic soap.....