OPStats stop working

aldous

Hi everyone,

A condo had 8 OPS-300 and they were all working fine. One of it dead and replaced with ViewStat. Yesterday, I finally get a communication wire to the ViewStat. After I connected the communication wire to the ViewStat and restarted the NXI controller, I can't get correct updates to the TP's. However, even I removed the communication wires from the ViewStat (back to original), I still have no correct updates on the TPs. "NOT CORRECT UPDATES" means that I'm getting some data on TP but not consistant. (e.g. I may see one or two of the OPS status on TP and may change some of the settings. However, not consistant...). I was able to "Send command" to any OPStat to change settings. I don't understand why it happen even I restored to original state.

Additional information about the configuration below:
- Address setting on OPS: 1 to 7 and the 8th is dead
- Address setting on ViewStat: 9 (but disconnected after I have problem)
- I am using the programming modules from AMX. The codes attached.

Could someone help, please? Thanks very much.
Aldous

DHawthorne

I've had lots of fun with these thermostats. Under certain circomstances, they can become very finiky, and if one stat acts up, it can take down the entire comm buss.

The below applies to using RS-232/422. I have never used them ISCNET, so can't comment on that.

For troubleshooting, I would recommend connecting to your master with a Telnet window, and turning on diagnostics, then send the command to the stat module to turn debug on. Set your computer up somewhere near the distribution panel. You should be able to see strings going back and forth from the working thermostats. Obviously, if the buss is frozen becasue of an errant stat, you are going to start with nothing. Another sign you still have a bad one on the buss is if you see a lot of garbage characters or nulls coming through. At the distribution, turn off all the individual thermostats. Turn on on, and wait a minute to see if it starts communicating properly. Then move on to the next until you find the one that is causing trouble. The key point here is that once one starts acting up, all of them need to be reset to talk again, so you must start out with all of them off.

Once you have the bad one isolated, you can just turn off it's communications and leave it powered on until you can replace it.

You might find that you can turn them all back on and have no problems, in which case it gets more annoying to deal with. You will have to turn off the comm on all the stats, then again turn just one on; wait however long the usual time it takes for a failure to show, and if none does, turn another on, etc., until the bad one makes itself known.

One other possibility is an HVAC unit problem. I have a system out there that has a noisy HVAC unit that periodically scrambles comm so I have to reset the entire system. I actually saw it happen while I was on the job. The HVAC people had the unit off while they were replacing something. I was monitoring the stats at the time, and the stats were all fine. The moment they powered up the HVAC, I got a burst of garbage data, then my comms locked up. Mind you, the stats power seperately from the furnaces, and you wouldn't think the data lines could possibly be affected by the relay closures to the HVAC unit - yet they were. I talked to Aprilaire about it, and got a tech to admit the comm uses a common signal ground with the HVAC relay common. So they are not really isolated, and an HVAC problem can screw up your thermostats. So I'm working right now on installing isolation relays to the output of the stats so this can't happen anymore. Enerzone used to actually make an outboard relay card just for this purpose, but it seems to have vanished since the Aprilaire changeover.

Kaptain Kaos

OPStats Stop Working

When mixing a Viewstat with the older OPS thermostats; the viewstat must be the last address on the buss and you must skip an address between the OPS and the Viewstat.

For example: 8 OPSs and one Viewstat. OPSs addressed as 1-8 and the Viewstat would be addressed as 10.

Good luck,

Rex

aldous

Thanks very much everyone here.

I finally find the defective thermostat and have others working now. But now, I have to make the viewstat works because OPS is not in production any more.

Question:
I had total of 8 OPS thermostats and now, I am replacing two of them with Viewstats. (OPS addressed to 1-6 and Viewstats to 8-9). What do I need to change in the programming? Should I set the "zone_cnt" variable to 9? or 8? Is it the only thing needs to be changed? Sorry to ask this because this is the first time I work on thermostats and I can't find the answer from the documents that I have.

Thanks again for everyone,
Aldous

DHawthorne

aldous wrote:

Thanks very much everyone here.

I finally find the defective thermostat and have others working now. But now, I have to make the viewstat works because OPS is not in production any more.

Question:
I had total of 8 OPS thermostats and now, I am replacing two of them with Viewstats. (OPS addressed to 1-6 and Viewstats to 8-9). What do I need to change in the programming? Should I set the "zone_cnt" variable to 9? or 8? Is it the only thing needs to be changed? Sorry to ask this because this is the first time I work on thermostats and I can't find the answer from the documents that I have.

Thanks again for everyone,
Aldous

I had a document detailing this, but I can't seem to find it. If it turns up, I'll post it. As I recall, there are only two things ou have to be sure of:

1) Your old stats need to have contiguous addresses at one end of the range. It has been posted here the new ones need to have the higher numbers, but that is not necessary, just that all your old ones need to be together. I can confirm this; I've done it making the new stat number one (in my install, number 1 was the one that died, and I got lazy ). So, if your old stats were 1-8, and number 5 was being replaced, you have to re-address the others to 2-8, and make the new one 1, or make the old ones 1-7, and the new 8.

2) You have to power them independently. You cannot use the old distribution to power the new ones. Break off the power leads and power the new stats with their own transformer.

Protocol wise, they work the same. There are some new commands available, but the old code will work with then new stats.

I might add, the original Opstats were flak at best. I don't have a single installation with them that includes all the original units, and very few that even include any of the original devices. I don't figure the average lifespan was more than 5 years; unacceptable, and very disappointing. A $20 Home-Depot thermostat lasts practically forever, and does more out-of-the-box. The new Viewstats seem far better, but I remain somewhat sceptical until I've had some in the field longer. I will say this: even the new Viewstats have some serious issues that make them somewhat disappointing. For one, any kind of comm buss glitch tends to make every stat on the buss go into a constant boot cycle; so, instead of just losing comm, you also lose HVAC control, making a very not-happy customer. I have been able to stabilize every system that had this issue, but it's really hard to track the individual fault when the whole system is blinking on and off. I have had various problems cause the same thing, from sending commands out to the buss too quickly to a faulty distribution board.

the field of communication thermostats is pretty small though, these things pretty much have a lock on the market. The ones you get from AMX are just branded; they were originally made by Enerzone, who has since been bought by Aprilaire; they are all the same devices.

vining

Has anyone tried the HAI communicating T-stats? I don't know if the comm protocol is published or strictly proprietary to the HAI control panel. They do have most of the same accessories, flush sensor, remote sensor, indoor/outdoor temp & humidity sensors, etc. They are a bit ugly though. Well maybe not ugly , maybe just cheap looking. The Aprilaire/AMX is much nicer looking IMHO.

I know some who have used the HAI and installed the HAI Omni Pro II control panel to interface with the T-stats using the AMX module to gain access and control and that was all the HAI panel was used for. No security or anything, just a bridge to the T-Stats. The PRO II can support up to 64 T-stats which should be enough for almost any application.

I've haven't gotten around to trying this or using the Viewstats for that matter but using an HAI panel to control there T-Stats may be cheaper and more reliable. But then again maybe not. (the reliable part, I'm sure they're cheaper).

Eventually I will have to try my hand at this and incorporate temperature control into my systems but I would appreciate if you guys would figure out the best methods so I don't have to suffer as you folks have done. Fortunately, I usually have an HAI panel in the house for security anyway so it wouldn't be an extra expense but I would like to know if it was either a better, worse or equivelent a method. From the sounds of things I can't imagine worse.

ericmedley

DHawthorne wrote:

...The below applies to using RS-232/422. I have never used them ISCNET, so can't comment on that....

I can comment on this. I have used them over ISCNet and a similar thing happens except that the comm errors soon overtake the whole NetLinx Master and it eventually locks up. Hopefully, AMX will get this little problem solved with the next firmware upgrade. It's kinda scary that a little ICSNet device can bring down the whole frame.

They [AMX - Aprilaire thermostats] are quirky but they're pretty much the only game in town. I have looked at other communicating thermostats. HAI makes one as well as Honeywell. Haven't tried them yet but would be curious of other's experience with them.