Honeywell wifi Tstat Problems...any solution?

vaporvac

For my recent install of twinned Slantfin TR50s, I went with the Honeywell RTH6580WF. I originally thought the wi-fi was just a gimmick, but I'm using it all the time. All the Honeywell models seem to be steam compatible, but I'm having a few problems that I didn't with my old Honeywell programmable Tstat. This one doesn't let me know how many hours a day the boiler has called for heat' I really liked that feature. I don't think they offer that anymore, it's just a change for the worse.
I also think these newer models are TOO sensitive to small changes in temp. It turns on the burners when the temp still reads at the desired setting, and then only for a few minutes. Definitely not enough to bring any steam to the rads. I don't even know why they fire since the Tstat seems to be met and the pressure is generally negative when the gas is off. It's a waste of gas and I don't know how to deal with it. I try turning off one boiler (the larger btu), and that helps a bit. I thought it might just be in the recent shoulder season, but it's happen now that it's quite cold. I'd love to hear others' experiences and possible solutions. I'd hate to have to get another Tstat. This had the two-stage that I needed for a pretty reasonable price.
I've yet to call hw about it.

nicholas bonham-carter

When I was down in the basement unloading the washer, I noticed the same sort of behavior from my Honeywell Visisonpro (non wireless, but with remote sensor). It runs the boiler for a few minutes, and then cuts out, more than once per hour. The temperature upstairs seems to remain constant, so maybe it is working as designed.
The other possibility is some sort of damage to it from the occasional static discharge when I have touched the screen. Maybe that has altered the CPH setting, even though I have verified the setup to be 1 CPH.
Maybe with your tag-team boiler setup, you could experiment with the CPH, as the system may emulate a hot water system, with the vacuum powered flywheel effect.--NBC

Canucker

http://yourhome.honeywell.com/home/Products/Thermostats/5-2-Day-Programmable/PRO+2000.htm#expand/collapse

The temp readout is covered in the FAQ section under "why does the thermostat temp not match my temp thermometer in my home?". It does some rounding on the display, so while you might not see the temp change, it actually has.

KC_Jones

Was just talking to someone about some of the annoyances of these thermostats. How about this one. 9:50PM fire boiler 10:00PM goes into setback...that was a waste of 10 minutes worth of gas. If I happen to hear it "click" I usually run over and manually turn it down right away. I haven't read a manual on mine in quite some time and maybe it isn't mentioned, but here is another question. How long does it have to be at a certain temperature before it fires the boiler? Like I open the front door and a blast of cold air comes in how long before it fires? I would actually be curious about this, or does this also tie in with the CPH setting? I guess this is sort of the same question as the OP?

KC_Jones

Changing the setback time would probably just make it worse knowing the way these things end up. I have bad news for Honeywell. I may be just some dumb customer, but my money is paying your salary. I tell my wife all the time. Tell me everything and let ME decide what is important.

vaporvac

Thanks all. I figured that's what's happening when it said it had +- 1deg accuracy. I'm just not sure how well that's working for steam or if there's any workaround. 10 minutes would get me somewhere, but 1 minute is nothing.

I'm also noting it's not really anticipating temp. ie. turning on early enough to reach temp by desired time, although I have that function activated. I may try the tech department; usually those folks love to discuss the specific workings of their products.
I'm both glad and bummed that the Visionpro has the same issues as that means there's no alternative with Hwll. Maybe when the Vstats are hooked up and the setting is changed to two-stage it will work differently.

It's also a shame there's no way to track the call for heat. MarkS, didn't you put something on your old burner a few years back? If so, how did that work out? I can't even figure out how to wire the lead/lag, but others may benefit from the idea.

KC_Jones

My Honeywell is an older (10 years) model and does all the same stuff. I would have to guess they haven't changed a whole lot functionally. How long have you had it hooked up. I remember mine took weeks before it was any good at anticipating. Now that I did my replacement it's learning again...lol. If you just hooked it up might want to give it a little time to see how it does.

Mark N

A thermostat is just a switch. Nothing more, nothing less. Colleen if you're set up for 1 cph it shouldn't fire up and turn back off. I have FocusPro set to 1cph and I have a data logger connected to my system. At 1 cph the cycles are consistently around 20 minutes in length, plus or minus a few minutes. Also, it is very consistent on how long it sits off in between cycles depending on the outside temp. Also, a thermostat has no way of knowing that no heat will be delivered to your system when it runs for 10 minutes then turns off because your setback time has been reached. Up till that time it is working off the the programmed set point.

vaporvac

Thanks markn. I guess it was you that had that hooked up the datalogger and not marks. I've set it for gravity steam which is normally 1cph. This new one doesn't give the choice of cph, just type of system, but on the last one steam was 1cph.
I know the Tstat doesn't know when steam heats the rads, but it cycles on continually and at very short intervals even when the pressure is in a vacuum. Heat doesn't even hit the rads, yet it will then shut-off as if the temp has risen. Maybe it has if I breathed on it. If anyone chimes in or pms me about wiring to stage my boilers (see other post: http://forum.heatinghelp.com/discussion/147642/stage-fired-boiler-controls#latest), I'll see if that makes a difference. glad to know i'm not the only one with these problems.
KCJones, I just set it up about 11/2 weeks ago so maybe not enough learning time.

Chris_L

You should check to see if this thermostat has a "swing" setting. That is the difference in temperature between when the thermostat turns on and if. So if you set it for 68 degrees, for example, does it turn on at 67.9 and off at 68.1 or is it more like 67.5 to 68.5?

I've found with my two steam systems, you have to pick the swing correctly. If the swing is too small, you get the kind of short cycling you describe, too large, and the thermostat overshoots the set point by too much.

In looking at other Honeywell thermostat models in the past, I found that you couldn't adjust the swing at all, so I bought others. I don't know about this one.

David Nadle

Newer Honeywell thermostats don't have a swing setting, but they use a pretty sophisticated learning PID control algorithm to maintain +/- 1 degree and figure out when to start to come out of setback. In place of a swing setting there is the CPH setting which limits the number of cycles per hour. If set properly for the type of system the Honeywell is in my opinion superior to a conventional thermostat with swing.

There used to be a Honeywell white paper on the web that explained how it all works. I agree that Honeywell should make information that differentiates their products much easier to find.

I'm not aware of any thermostat that will cancel a call for heat because setback is scheduled to start "soon." How soon is too soon?

KC_Jones

David Nadle said:

I'm not aware of any thermostat that will cancel a call for heat because setback is scheduled to start "soon." How soon is too soon?

Give me the setting I can decide for myself. In all honesty with the learning function it knows how long it takes to change the temp by a given amount in a given time so if it's 10 minutes until setback and it already knows it can't do anything in 10 minutes seems pretty straightforward to me. I am not trying to down Honeywell just voicing a complaint I have about an otherwise great product. I work in the industrial HVAC market I have nothing but respect for Honeywell, but nobody is perfect.

David Nadle

KC_Jones, I think it's a great idea.

ChrisJ

KC_Jones said:

Was just talking to someone about some of the annoyances of these thermostats. How about this one. 9:50PM fire boiler 10:00PM goes into setback...that was a waste of 10 minutes worth of gas. If I happen to hear it "click" I usually run over and manually turn it down right away. I haven't read a manual on mine in quite some time and maybe it isn't mentioned, but here is another question. How long does it have to be at a certain temperature before it fires the boiler? Like I open the front door and a blast of cold air comes in how long before it fires? I would actually be curious about this, or does this also tie in with the CPH setting? I guess this is sort of the same question as the OP?

I bet as soon as Mark S read this he said "Chris J".
I constantly complain about this and have for years.

As far as how soon is too soon? 5 or 10 minutes is fine for probably every system out there. Or, connect it to the system type which many "smart" thermostats ask you about now. If you're going to do a setback at 10PM, there is clearly no point in turning the burner on at 9:55PM whether it's forced hot dust,steam or radiant.

KC_Jones

ChrisJ said:

If you're going to do a setback at 10PM, there is clearly no point in turning the burner on at 9:55PM whether it's forced hot dust,steam or radiant.

Maybe a bonfire in the living room would do it?

David Nadle

I think an average of the last 3 days' cycle times would be a good estimate.