Another Harman Room Temp/Auto ??

[Mainiac]

I have a 2006 Harman Accentra 2 FS that I am running in a 32x24 log home built in 2008. Half the house is open floor to ceiling with an open loft in the other half and two bedrooms on the first floor under the loft area. I have extended my room temp probe (new) to be next to my oil burner thermostat just outside the door of the bedroom in the back corner of the house and down a short hallway. The total extension probably added 10’ of wire.

The temps here this week have been running in the high 30’s to low 40’s at night and into the mid 50’s during the day. With the room temp dial set at 68 degrees and auto ignite, it will keep the house comfortable during the day and evening ramping up and stalling down and even eventually shutting off completely during the night sometimes. My problem seems to be that when I get up in the morning and look at the oil burner thermostat it indicates the room temp is 64 and I keep feeling the stove should have kicked on and it is not. I will admit to being a NOVICE and still trying to fine tune my understanding of properly setting up the stove but does this sound correct? Is the thermostat or room temp dial tolerance greater than 3-4 degrees? Is the open floor plan not conducive to the current placement of the temp probe? Is it just that it is the “Shoulder Season” and I need to give it more time to get consistently colder?

I have read and re-read all the Room Temp/Auto threads I could find and am just still a little confused. I went completely through the stove cleaning the entire exhaust path including the ESP as well as the rest of the stove prior to installing.

 

[Bioburner]

I was concerned about almost the same issue so I bought a cheap temp gauge with a extended probe and taped it together with the stoves probe and found the issue was the original wall stat.

 

[alternativeheat]

There is probably variation between the stove setting and the house stat is all. If you are used to feeling what the house stat reads then just bump the stove up till it satisfies that need. Don't worry that the control at the stove has to be set higher as long as you are comfortable. I actually do this with the probe setting behind the stove.I run the stove so the house reads 73 ish in my dining room where the house stat is.

Also understand that the stove is not going to heat like central heating heats. The central heating system is likely more even throughout the house.

 

[Tonyray]

There is probably variation between the stove setting and the house stat is all. If you are used to feeling what the house stat reads then just bump the stove up till it satisfies that need. Don't worry that the control at the stove has to be set higher as long as you are comfortable. I actually do this with the probe setting behind the stove.I run the stove so the house reads 73 ish in my dining room where the house stat is.

Also understand that the stove is not going to heat like central heating heats. The central heating system is likely more even throughout the house.

Exactly what I do....
use the wall thermostat to get true temp...
probe taped behind the hopper.

 

[Mainiac]

I was concerned about almost the same issue so I bought a cheap temp gauge with a extended probe and taped it together with the stoves probe and found the issue was the original wall stat.

Would I get the same measure of variation if I were to just shoot the room probe with my Fluke laser temp gun and compare that to what the burner t-stat right next to it is reading?

Also understand that the stove is not going to heat like central heating heats. The central heating system is likely more even throughout the house.

I could have been clearer as to my previous heating methods. Even though we built the house with oil heat we have always heated primarily with wood and this year have decided to experiment with a pellet stove. Hoping to eliminate all the work and mess of wood and also get more linear heat as opposed to the ups and downs of wood heat.

I'm thinking the solution is going to lie with what others have mentioned already in addition to perhaps moving the probe back a little closer to the stove and even a strategically placed fan or two given the open layout.

 

[alternativeheat]

Would I get the same measure of variation if I were to just shoot the room probe with my Fluke laser temp gun and compare that to what the burner t-stat right next to it is reading?



I could have been clearer as to my previous heating methods. Even though we built the house with oil heat we have always heated primarily with wood and this year have decided to experiment with a pellet stove. Hoping to eliminate all the work and mess of wood and also get more linear heat as opposed to the ups and downs of wood heat.

I'm thinking the solution is going to lie with what others have mentioned already in addition to perhaps moving the probe back a little closer to the stove and even a strategically placed fan or two given the open layout.

Like Tony I have my room temp probe taped to the hopper back up as high as I can get it. I coiled the wire up and let the probe itself sit out to the side about 3 " or so. I adjust the room temp so the dining room is around 73. It will run for months like that never changing a thing except to shut down for cleaning or if I want to run in stove temp for some odd reason.

Of course that is when I'm using the stove. With pending knee surgery, oil at $1.95 a gallon, warm fall, there has been no need for the stove yet this year.

 

[bogieb]

The room temp set for the main floor P43 is at 65* and my room thermostat reads anywhere from 72-78*. The room I actually guage the temp off of stays 70-73*. If I cared to, I could move the probe higher so it was more in line with the temp I trying to keep, but it works fine the way I have it set up, so don't bother.

The room temp for the basement P61a is set at 70. There I have the probe stretched out up and toward the front (the end is tied to the front of a shelf). I can't have that thing to the rear of the stove, or lower as then it picks up the cold off the foundation (or concrete floor). So, I moved the probe around until it was at a place where I felt it kept the temp swing to a minimum for that environment.

 

[Husky]

If your going to run in temp/auto you should add a milli volt wireless thermostat to your unit. I hooked one up in series with my temperature probe and place the thermostat out in my room where we are living, close to furnace thermostat. The thermostat can be about 15-20 feet from the stove. The other nice thing is you can have 4 set back times and temperatures to control your stove. For example I have stove kick on at 4am and then shut down at 7am to have living space warm in the morning when we are getting ready for work and then have the stove kick back on at 4pm and kick off at 9pm so house is warm when we get home and shut back down at 9pm when we head to the bedroom. When it gets real cold I will just have stove turn down to lower temperature instead of shutting down. If your using your stove like a main heating source this really help you control your environment. Real simple to install and only takes maybe 15 minutes.

 

[alternativeheat]

If your going to run in temp/auto you should add a milli volt wireless thermostat to your unit. I hooked one up in series with my temperature probe and place the thermostat out in my room where we are living, close to furnace thermostat. The thermostat can be about 15-20 feet from the stove. The other nice thing is you can have 4 set back times and temperatures to control your stove. For example I have stove kick on at 4am and then shut down at 7am to have living space warm in the morning when we are getting ready for work and then have the stove kick back on at 4pm and kick off at 9pm so house is warm when we get home and shut back down at 9pm when we head to the bedroom. When it gets real cold I will just have stove turn down to lower temperature instead of shutting down. If your using your stove like a main heating source this really help you control your environment. Real simple to install and only takes maybe 15 minutes.

I learned decades ago that in this house recovery takes far too long to be swinging temps several times per day. Better off ( money ahead) to keep it constant all winter long unless going away for a week. In this house you don't want to give cold a chance to creep in, then you gotta drive it back out. Each house , each situation is different.

 

[Tonyray]

I learned decades ago that in this house recovery takes far too long to be swinging temps several times per day. Better off ( money ahead) to keep it constant all winter long unless going away for a week. In this house you don't want to give cold a chance to creep in, then you gotta drive it back out. Each house , each situation is different.

house recovery takes far too long to be swinging temps several times per day.
Agree 100%.
That is really Key to keeping a house warm IF it's not tight as a drum via Insulation as many are not..

 

[Bioburner]

house recovery takes far too long to be swinging temps several times per day.

Well we are using a room fan one tenth the size or less than a house furnace. Hard to beat CFM when trying to recover. Read somewhere that one should not swing a home furnace more than 8 degrees unless more than 8 hours

 

[alternativeheat]

Well we are using a room fan one tenth the size or less than a house furnace. Hard to beat CFM when trying to recover. Read somewhere that one should not swing a home furnace more than 8 degrees unless more than 8 hours

Not too different from my experience.. I just found it to pay to leave the thermostat alone, a long time ago. In my house if you let the house cool down, it's a long recovery and it doesn't end on just one cycle. The furnace ( for instance) cycles off and then it's back on again not too long later as the cupboards, any glass, the very walls have not quite come up to temp yet just cause the air has. Then finally just as everything stabilizes and it shuts down again to cool off all over again. Makes no sense. A stove is all the worse , it doesn't have the CFM or BTU of the furnace. Nope I tested fuel consumption decades ago, it was less costly over the winter to leave the thermostat alone, less cycling and shorter cycles on with longer cycles off..

 

[Bioburner]

Thermal mass enters the picture your talking about.

 

[bags]

IMHO thermal mass is the key. Maintaining that is way better than going from cold to hot just to achieve warm enough. I am a strong supporter of the cruise control function. Just a nice way to consistently arrive at that destination.

I will add that during the shoulder seasons it can be strictly a judgement call though. You can shut the stove down and quickly get back up to cruising altitude without much fuel consumption......... Relatively speaking. During the cold it requires much more and this is where it turns into a no brainer for me to keep the stove rolling along and just maintain the comfort zone.

Flip flops aren't so great in the snow and that is just a bummer. Wonder what the pajama wearing peeps at Wally World are going to do? LOL!

 

[Peterfield]

house recovery takes far too long to be swinging temps several times per day.
Agree 100%.
That is really Key to keeping a house warm IF it's not tight as a drum via Insulation as many are not..

I spoke with a pellet store owner who had a bet with his then fiancé, now wife, about this topic. He bet her it would take less pellets to heat their house keeping the temperature constant rather than turning off the stove when they weren't home. They burned for a week using each methodology and he won the bet. His take is if you let the house cool off, you have to reheat all the objects in the house as well as the air and it takes more energy than just keeping everything at temperature. He said he used four less bags of pellets his week than her week.

 

[Bioburner]

City driving versus highway

 

[Husky]

I agree that every situation is different. I agree that letting your house cool down to much will take a long time to bring everything in house up to temperature. In my situation I use my NG furnace to bring things up to temperature and then use stove to keep things warm in our living area. I do not use the stove to try and heat my house. We like to have a fire for the ambiance and warmth for the room we spend all our time in. This is why the thermostat works for me with set backs. I do let my house drop down to 58 when we are away at work, which is about 8 hours. Then I have furnace and stove kick on to get things back up to temp. I have always used the premises that if you can drop temp in house for 8 hours it is worth dropping 10 degrees.