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gdhannah
Dec 15th, 2005, 08:09 AM
I'm looking for more information on the settings for my programmable thermostat. I'm experiencing overheating - the thermostat is in the centre hallway in my house, and the heating is on the baseboard all around the outside walls. I have the heat set to 21 degrees from 5:30 am until 7:30 am.

The problem is, the outside rooms hit 26 degrees before the thermostat registers 21. In a closed bedroom on the outside wall of the house, you nearly suffocate while the thermostat is calling for heat. This wasn't a problem with the old thermostat, because it called for heat on and off all night. With the programmable, though the house has cooled overnight. Everyone wakes up with a sore throat from the dry air and the heat in the bedrooms.

I turned off the cycling feature of the thermostat. Would it help to turn it back on? It didn't work well in the fall, but maybe now that we're into the heating season, it would work better? My furnace is electric, but it heats water, and runs it through baseboard radiators. I'm not sure which cycling setting is correct. The options are:

Cr0 - disabled
Cr1 - hydronic heat, condensing gas furnace (2 cycles per hour)
Cr2 - Commercial unit (3 cycles per hour)
Cr3 - Gas or oil forced air (5 cycles per hour)
Cr4 - Electric heat (7 cycles per hour)

With this option set to Cr3, the default, the furnace cycled too much, turning off before significant heat got to the rooms. At Cr1, it was better, but still seemed to cycle too often.

With my furnace, the thermostat has to call for heat for at least 10 minutes just to get up to pressure, and heat the water in the pipes.

mlc2000
Dec 15th, 2005, 12:16 PM
Doesn't Noma have a 1-800 number?

gdhannah
Dec 18th, 2005, 09:10 AM
Doesn't Noma have a 1-800 number?

Their hotline appears to be for installation issues only. They haven't responded with anything useful.

djpositivek
Dec 18th, 2005, 10:06 AM
I'm curious about this as well... I have Noma programables and am not sure which setting is best. I have an oil fired furnace that heats hot water and runs it through baseboards in the basement and in-joist on the main floor and 2nd floor. I'm not sure what setting it's on now, it was installed by the electrician when we moved in a year ago. I know the small instruction booklets aren't very informative. Took me forever to find out how to change the display from F to C.

tlamm
Dec 18th, 2005, 07:00 PM
Buy a seperate thermostat device to see what the temp in the hallway really is. Perhaps it does not reach 21 until the other rooms reach 26. Maybe you will need to lower temperature?

jed
Dec 18th, 2005, 10:47 PM
Usually theres a "sensitivity" setting where you can adjust how long the furnace runs, and how frequently. I played with mine so it stayed off a bit longer, before coming on - perhaps yours has such a function? Mine was a screw with a non-programmable and it took a bit of rigging before I got it.

gdhannah
Dec 19th, 2005, 09:38 AM
Buy a seperate thermostat device to see what the temp in the hallway really is. Perhaps it does not reach 21 until the other rooms reach 26. Maybe you will need to lower temperature?

You're absolutely right. When bringing the temp up from the overnight setting, the temp in the hallway reaches 21 when all the other rooms are 26... Problem is, once it's up to temp, the rooms cool down to 18, say, and the hallway is 20. I guess the real answer is to move the thermostat into one of the rooms instead of the hallway...

The important thing is, with the old thermostat, the house was too warm at night, and I think it worked on a +/- 5 degree error rate, while the noma keeps it within a couple degrees most of the time (except the morning warm up).

I've actually found that setting the heat to come up at 5:50, then down for the day at 6:30 works well. This warms the house up a few degrees from the overnight temp, but it doesn't have time to overheat, but the house stays at a pretty good temp until everyone leaves.

RedDeer17
May 2nd, 2008, 06:52 PM
I have installed programmable Noma thermostat.
I've noticed the weird thing too. I set it to heat and set desired temperature to 20C . The actual temperature reached 20.7 but it continued to cycle furnace every 2-5 min for short period of time. I would think that if the current temperature higher than desired it should not initiate heat at all.
Anybody was experiencing the similar problem?

tlamm
May 2nd, 2008, 07:50 PM
I have installed programmable Noma thermostat.
I've noticed the weird thing too. I set it to heat and set desired temperature to 20C . The actual temperature reached 20.7 but it continued to cycle furnace every 2-5 min for short period of time. I would think that if the current temperature higher than desired it should not initiate heat at all.
Anybody was experiencing the similar problem?

They all do that. If they stopped at exactly 20C they would cycle on and off constantly.

monomono
May 5th, 2008, 09:44 AM
I had the same problem with a Noma 7 day. I wasn't happy with it overall (except for the $20 price). I replaced an ancient Honeywell box which actually did a much better job of maintaining the temperature.

The Noma seems to work as follows:
- As long as the room temperature is within 0.5 degrees of the set temp, it will continue to call for heat.
- It will call for heat as often as you set the cycle rate setting. But the duration that the heat stays on for each cycle depends how far off the set temp you are.
- If room temp falls 0.5 degrees below the set temp, the unit goes into 'recovery' mode. The heat will stay ON permanently until it gets to 0.5 above the set temp. This really sucks IMO, because keeping the heat on for so long is going to make some rooms way too hot.

Setting the unit to farenheit is the only thing you can do to improve the accuracy, because 0.5 degrees F is less than 0.5 degress C. But in general I would not buy a Noma thermostat again.