Programmable Thermostat with Ramp

nting this?

My questions were asked civilly. I asked why you cared about my reason for wanting to do this. Can't you answer a civil question? I would point out that you simply should not respond to trolls at all.

I'm looking to optimize my electrical usage. That's all. The money involv ed is likely minimal, maybe $1 a day. When my ToU peak period is over I ge t notices that my electrical usage in that hour has exceeded a threshold th at I set to inform me that the backup heat is likely running, 10 kWh or som ething like that. That is wasteful and not needed, so I'd like to eliminat e it.

I honestly thought this is something that has happened to many other people and there likely was a thermostat available that would handle the issue. If all I needed to do was pay $50 or $100 for a new thermostat, then Bob's your uncle. But it would seem no one else here has ever given any thought to the matter, so I am in the same place I was before I asked. Ok, so I'l l ask some professionals and/or keep looking at available units.

Straight electric heat is not inexpensive though. One winter when the temp

it cost me about $60 for those three days... before I switched to ToU billi ng. But that's not why I switched. I expected to save some money charging my EV. Turns out I mostly charge for free at the Superchargers since char ging at home doesn't do a lot for me. But I optimize my usage partly to lo wer my bill but also to help lower the coop's costs. There's a reason why they charge more at peak time, because they are paying more for electricity .

Analyze away!

it might suffice to use a thermostat with a setback, that accepts a 5C lower temperature during the high-energy-cost hours. The problem is, keeping the thermostat coordinated with changes (and the seasons: you might want to bump the setpoint UP in summer if cooling costs count). Making things 'far more intelligent' means they'll trick me.

I still grit my teeth when the cloud does its thing behind my back...

If you read my posts, especially the original post, you will find that is exactly what I am doing. I am using a programmable thermostat to drop the set temperature low enough that it does not come on during the peak time.

The issue I am having has been explained several times including the original post.

Well, like you say, finding a properly programmable model is a hard aspect to discover. My Carrier thermostat might work, but it might not.

To my mind, delaying switch-on of the backup heat isn't very intrusive. It'll think it has added extra heating, and keep on doing its regulating job. It'll just take a little longer, as you've ordained, but it won't know about your thwart, or if it does, it won't be able to do anything about it. I like the simplicity of it. Man over machine!

You retain all the smart features of your thermostat, seasonal and hour-by-hour timing, UV control, humidity control, etc.

whit3rd wrote in news: snipped-for-privacy@googlegroups.com:

snip

Like fashion up a nice big bolt of lightning? :-)

Is there anthing you can do to make the heat pump produce more heat? (have you found anything, or am I just restating your question?)

What is the interface from the thermostat to the heat-pump? is it just one wire for 24V AC, one wire for heat, one wire for fan, and one wire for ground?

nditioning during the peak usage times as set by the ToU billing with my ut ility. The problem I have is the heat pump not ramping up the temperature fast enough when it comes back on and the backup straight electric heat com ing on. This uses maybe three times the amount of electricity during the t ime it takes to get up to temperature.

f. I'm wondering if anyone makes a programmable thermostat that deals with this issue. If the problem is caused by the thermostat not letting the he at pump run long enough that is easy to fix. If the problem is caused by t he heat pump itself, then the way to deal with it is for the thermostat to run the heat pump in bursts short enough to keep the back up heat from runn ing.

I'm not sure what you are asking. Heat pumps tend to be on/off arrangement s. I've seen something about two stage heat pumps, but whatever that is, I don't have one. So the way to get more heat out of the pump is to run it longer. But that's not the issue. The heat pump isn't "straining" or unde rsized. It just has to run for a while in order to bring the temperature u p and the thermostat is designed to treat that as a condition where it need s to run the backup heat.

Like some of the other posters, I have no idea where you are going with thi s.

I haven't taken it apart, but I'm sure it's the standard heat pump with ele ctric backup wiring arrangement. There are actually a number of wires, one for heat, one for cooling, one to run the fan, one to bring in power and I believe a common.

I would only care about that if I want to roll my own thermostat.

Again, where would you be going with this?

It's perhaps an off-the-wall idea, and may not be esthetically acceptable for your living space, but you might want to consider using an industrial temperature controller. Some of them have programmable ramp-and-soak capabilities.

I suspect the only real solution to this thermostat issue is an Aurdino or similar device with thermal sensors that can monitor temperatures and have an algorithm that compensates for outdoor vs indoor temp and either allows the heat pump to over-ride as the primary source, or if the temperature is below the optimum or falling at a rate that would negate the heat pump then switches to other source of heat.

Some programming is required...

John :-#)#

rk,

ep

ger,

ike

You might want to start here for ideas:

John :-#)#

The problem is not the setback. The problem is that if the temp drops more than a couple degrees, the typical thermostat for a heat pump then kicks in aux electric heat to help close the delta. Which is one reason many, maybe most heat pump homes don't set them back at night.

thermostat.

of thermostats, but all the hype and BS gets in the way of seeing what many of them actually do. Even Consumer Reports doesn't seem to have considere d this issue and they seem to reflect what the thermostat makers provide, s o maybe it's not out there and I need to roll my own.

at might be a good choice, but I'm not ready to start designing just yet.

The only way you're likely to find that level of detail is to download the install manuals for various possible thermostats.

If I were the thermostat maker, I would include a setting where it estimates how long it will take to close any given delta using only the heat pump and give you the ability to say that if that time is less than X minutes, then don't use aux heat.

You don't need a high current contactor, unless Carrier is doing something proprietary to screw you. Normal thermostats have a low voltage wire that calls for aux heat. If you want to disable it with a hack, just use that.

My 3-ton R410a heat pump condenser, which maybe cost $3.8k, goes full-blast when running, draws 5kW from 230Vac, and chills the outside air 5kW worth. The only way to increase its heating rate would be to replace it with a bigger model.

Looks like that should be more like $1.8 to 2k. But of course we don't know exactly how much of our HVAC rebuild price was due to the heat pump. I recall mention of an extra $800 charge for a heat pump over a simple compressor, easy choice.

e thermostat.

h of thermostats, but all the hype and BS gets in the way of seeing what ma ny of them actually do. Even Consumer Reports doesn't seem to have conside red this issue and they seem to reflect what the thermostat makers provide, so maybe it's not out there and I need to roll my own.

That might be a good choice, but I'm not ready to start designing just yet.

Just as thermostat makers give nice, fancy terms to the early onset to ramp the temperature up, I would expect a feature like this to have a nice, fan cy name and in particular note the savings in cost by not kicking in the ba ckup heat. So, no, while it may require reading a *lot* of ad copy, I don' t think it will require reading "install manuals". In fact, having read a number of "install manuals" over the years, I don't think that info would b e in them unless it was programmable in some way.

But there's only one way to tell for sure. I would contact an installer, b ut from the blank stares I'm getting from this crowd I rather doubt the ins taller community would understand what I'm talking about. My previous enco unters with the HVAC crowd tells me they are not the most intellectual crow d often knowing much less about topics than I do. But they have the experi ence I don't and they know the jargon I don't. Sounds like doctors.

Disabling the backup heat won't necessarily work anyway. I had a heat pump backed by an oil burner. The oil burner stopped lighting one day and the system just didn't work. Seems they turn off the heat pump when running th e back up heat and if the backup heat doesn't work you are then stuck with no heat even though the primary heat works!

Yes, our system works that way.

I'm trying to identify the problem space.

If the thermostat can't call for extra heat (more neat the regular heat) it also can't control what the heat-pump does to provide the heat.

Perhaps the compressor is reading something into it length of the heat command. maybe if you blip the heat command off for 30 seconds every 15 minutes it won't fire up the resistive heater.

If it can call for extra heat you'll need a script that queries the thermostat for the current temperature (I expect a smart thermostat knows the current temperature) and then puts the set point just a few degrees warmer so that the thermostat doesn't go into rush mode and ask for extra heat (just ask for regular heat).