Honeywell TH8000 Thermostat - Won't Allow Me to Set Temp Below 68 Degrees

[LucidLuniz]

The subject pretty much says it all.

I have a Honeywell TH8000 thermostat which won't let me set the temperature below 68 degrees.

I've read through the manual and checked to see if anything is locked (it's not) but am not sure where to go from here.

My guess is that this is something simple but I've not been able to figure it out. Can somebody please provide some assistance?


Thanks in advance!

[ADillon]

The installer set the minimum range for cooling to 68. It has to changed in the installer's set up. Likely he did that because the system is not designed to keep the space below 68.

[ADillon]

Ooops i wasn't supposed to post in AOP..sorry guys!

[LucidLuniz]

Is there any way I can bypass what the installer set as the minimum? This is for a supplemental AC to cool our server room in the evenings when our building shuts off the ACs to save power.

When I was working the other evening I noticed that it was getting extremely warm in the evenings as a result with the temperatures rising as summer sets in.

[LucidLuniz]

Ooops i wasn't supposed to post in AOP..sorry guys!

Well it was helpful for me to know in any case. Thanks for that useful information.

[Stamas]

You would have to refer to the installer's set-up guide. But making it go lower will not make the system work harder. If it's not keeping up when main system is down this system may have a problem or can't handle the load.

[beshvac]

You would have to refer to the installer's set-up guide. But making it go lower will not make the system work harder. If it's not keeping up when main system is down this system may have a problem or can't handle the load.

:ditto:

Thermostat is just like a light switch....its on or off....If its on and can't keep up, it won't keep up if you set the thermostat to 10 degrees :)

[Stamas]

You would have to refer to the installer's set-up guide. But making it go lower will not make the system work harder. If it's not keeping up when main system is down this system may have a problem or can't handle the load.

[Six]

Its set there for a reason. If your Ac isnt keeping up maybe you need to call a service company.

I cant think of any comfort cool application that necesitates temps below 68 degrees

[LucidLuniz]

Sounds good, thanks for your help everybody. I'm going to call a technician and get them to come check out our AC.

Much appreciated, this is a far better response than I was anticipating!

[Sleuth]

.

Has anyone changed the air filter lately?

..
:angel:

[LucidLuniz]

.

Has anyone changed the air filter lately?

..
:angel:


Unfortunately there doesn't seem to be any documentation on how the system was setup or maintained. It is in an office building so I'm not even sure where the air filter is...will have to see what I can find, thanks for the recommendation!

[glennac]

Can't understand the big fuss here. It won't hurt nothing setting the temperature lower than 68. It will either cool it down say to 66 or what ever or it won't. No issue. I'm sure on a real hot day it will not but on a day several degrees less than design outside air temperature for cooling it should go lower.

It may not get there during the day depending on how hot it is outside but hopefully it will go down at least at night and you can sleep extra cool if that is your desire. Thank you, thank you very much

[wahoo]

Many residential split system AC units are not designed to operate below 70 degrees. If turned to below 70, then the indoor A coil may accumulate ICE, and once it starts, it'll simply freeze A coil over (usually in the middle of the night!). The next call will be to an AC company with complaint of "no air blowing", and resulting charges and problems. Sure the homeowner can set the thermostat wherever they want, but if below 70 then get ready for problems!!:gah:


Yep, after Tech. "solves" froze up A coil, he'll say "Thank you, thank you very much"!!!!

[motoguy128]

Its set there for a reason. If your Ac isnt keeping up maybe you need to call a service company.

I cant think of any comfort cool application that necesitates temps below 68 degrees


Or even 70F for that matter. If you doing even a halfway descent job of managing humidity.

Personally, where I work, I tell everyone if it's set under 70F, you run a risk of freezing the coils. I'f getting close to buying password protected thermostats in bulk. I'm constantly finding units set to 67F or lower.

[motoguy128]

On my unit at home, I set a lower limit of 70F for the AC. For heating, a lower limit of 60F and upper limit of 75F. My actual setpoints are much narrower than that. Those are just the limits for my family members if they start button pushing.

Carrier Infinity System don't even allow airflow reduction at all for dehumidiifcation under 70F in it's internal logic.

[glennac]

Many residential split system AC units are not designed to operate below 70 degrees. If turned to below 70, then the indoor A coil may accumulate ICE, and once it starts, it'll simply freeze A coil over (usually in the middle of the night!). The next call will be to an AC company with complaint of "no air blowing", and resulting charges and problems. Sure the homeowner can set the thermostat wherever they want, but if below 70 then get ready for problems!!:gah:


Yep, after Tech. "solves" froze up A coil, he'll say "Thank you, thank you very much"!!!!

Funny I'm running mine on 67 during off peak hours (5 cents a kwh) and from 2 til 7 pm I have it set for 77 F (19 cents a kwh) never have had a freeze up and it is charged right. Maybe some of the higher efficiency units or 410A may have this problem and if so then just set it as low as you can go without freezing up.

Don't need to be a rocket scientist here. There is no overall rule that you have to stay at least 70F or above on all units. Again, thank you, thank you very much

[Six]

Can't understand the big fuss here. It won't hurt nothing setting the temperature lower than 68. It will either cool it down say to 66 or what ever or it won't. No issue. I'm sure on a real hot day it will not but on a day several degrees less than design outside air temperature for cooling it should go lower.

It may not get there during the day depending on how hot it is outside but hopefully it will go down at least at night and you can sleep extra cool if that is your desire. Thank you, thank you very much

The abillity to lock out the consumer from freezing up their coil and damaging their sheetrock is brilliant.

[glennac]

The abillity to lock out the consumer from freezing up their coil and damaging their sheetrock is brilliant.

Funny if you built it to code you can't damage your sheet rock, brillant.

Now several of my customers like it cooler. I didn't feel like I would have to right a paper on this. I do explain to them that if you like it cooler then you may get a freeze up and in that case set it higher. I don't lock my customers out unless it is a rental or they just can't understand. I treat most of them with respect and not like two years olds who can't make any decisons on there own.

I have never had a call back because the unit was freezing up due to a low temperature setting. I'm sure there may be a first time but if that happens I will deal with it and I will continue to treat most of my customers as adults until proven otherwise. I hope I have made myself clear here and you all are welcome to block them out all you want. Thank you, thank you very much

[wahoo]

We had a call earlier this week on a long term landowner's property where the renter was "insisting" that she wanted the house to be 65 degrees and she couldn't understand why she could not have that. We priced the landlord a freeze protection thermostat. We'll hear back probably. Happens fairly often here! If you wish to attempt to "educate" a early 60s renter who is probably having health issues (along with nerve problems) then have at it!! Sadly we are not in that business.:gah:

Our recommendation? Yep, just install a freeze protection thermostat (FSP) and let her do whatever she desires!

[LucidLuniz]

I'm not in the HVAC business but my curiosity is getting the best of me.

Can you guys explain what part would cause the pipes to freeze? I've actually done this before at my home but instead of calling a technician I just pulled the fuse on the AC for a few hours until it unthawed.

I was under the impression that this was due to the freon being low or the protective sheath around the pipe being cracked, exposing it to warm air and moisture. However, perhaps this was simply due to me setting the thermostat too low?

[glennac]

We had a call earlier this week on a long term landowner's property where the renter was "insisting" that she wanted the house to be 65 degrees and she couldn't understand why she could not have that. We priced the landlord a freeze protection thermostat. We'll hear back probably. Happens fairly often here! If you wish to attempt to "educate" a early 60s renter who is probably having health issues (along with nerve problems) then have at it!! Sadly we are not in that business.:gah:

Our recommendation? Yep, just install a freeze protection thermostat (FSP) and let her do whatever she desires!

That's a good solution. I've been lucky and haven't had problems with my units freezing due to customers setting the temperatures real low. 65 is low.

Now Luci if your unit freezes up then turn it off and put the fan from auto to on so the ice will melt quickly. You should then check your filter and see if it needs changing. This can cause freeze up that is lack of sufficient air flow across the evap coil. If that's not the problem then check your thermostat setting and keep it above 70 and if it freezes up again call your AC man you might need some Freon.

[wahoo]

Glen's covered most of it, but DON'T use 1" pleated air filters either as their high air flow restriction can also cause frequent freeze-up problems!!:putergreet:

[LucidLuniz]

I work in IT and make frequent use for forums as a result.

This may be the most helpful forum I've ever posted on and it's not even IT-related.


Thanks everybody, you guys are awesome.

[jpsmith1cm]

I'm not in the HVAC business but my curiosity is getting the best of me.

Can you guys explain what part would cause the pipes to freeze? I've actually done this before at my home but instead of calling a technician I just pulled the fuse on the AC for a few hours until it unthawed.

I was under the impression that this was due to the freon being low or the protective sheath around the pipe being cracked, exposing it to warm air and moisture. However, perhaps this was simply due to me setting the thermostat too low?

Low refrigerant charge, low airflow or setting it too cold can cause icing or frosting of the lines.