T-stat not working ? PDVC

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chrisasst

Minister of Fire
Aug 13, 2008
1,289
cortland ny
So bought a new Tstat a few days ago has been working fine. Last night I thought it was not shutting down. I come home today, my house is about 80+. Tstat is set at 70. That also says the temp is 80 degrees. I know I probably should ask mike H. but maybe if any of you know this question.. Will a Tstat on the PDVC not work if the LFF is too high or if the heat setting is set on a lower setting ( 2 or 3). With my test yesterday I left my settings at 7-5-1 heat setting #2.


BTW with those settings I went through about a bag of pellets in 12 hours vs the usual 8 or 9 hours when I have it at 5-4-1 with higher heat #. So if any thinks you are going through alot of pellets, try a higher LFF and lower heat # to see.

Anyway, any one know the answer before I PM mike...
 
pdvc with a stat;
the stove when hooked to a stat will work in a "high/low" manner, meaning that when you run the stove and set the stat to a temp it will try to hold at that temp by cycling between the heat range you select on the board, and low or "1" though the numbers do not change on the board and the "blower speed is not affected.

so, the OP said he is running on heat range of 2 so what would happen is that when the setpoint on the stat was reached (the temp he picked on the stat) the stove would slow down the same as if the heat range was lowered to a "1" and continue to burn at that rate until the stat called for heat again, in which case it would revert back to heat range 2 that the OP was running on.

so, the stat could function normally and not show a major difference in output when it changes.
 
So maybe my Tstat is not working 100%... Because the stove was definetly not cutting off. The Tstat was set for 70 degrees and the Temp was 80 degrees and the stove was going strong.
 
Are you sure you set the stat up right? and level?

Try setting the stove to 3 - 2- 1 and retest.
Make sure the fan doesn't shut off after the temp reaches about ~4 degrees higher than the stat is set to.
If it does go off then try 4 - 3 - 1

After the stat reaches the desired temp it will open the circuit and the stove will go to those low settings. Watch it for several cycles. It will waste pellets if it is short cycling or the stat is too far away from the stove.
 
chrisasst said:
So maybe my Tstat is not working 100%... Because the stove was definetly not cutting off. The Tstat was set for 70 degrees and the Temp was 80 degrees and the stove was going strong.


the stove AINT gonna cut off, its a "high/low" system , not an on off system
 
stoveguy2esw said:
chrisasst said:
So maybe my Tstat is not working 100%... Because the stove was definetly not cutting off. The Tstat was set for 70 degrees and the Temp was 80 degrees and the stove was going strong.


the stove AINT gonna cut off, its a "high/low" system , not an on off system

YEs I know, Usually when it kicks in low the flame is almost gone. Not this time
 
What stat are you using some of them need a lot of settings programmed into them.

I just finished doing that with mine and it wanted 4 settings per day, you miss a few and it may not be set where you think it is.
 
It is programmed correctly. It was working fine. Now all of a sudden today, after testing different LFF and heat #'s, it is not working. I turned the stove off at about 4 to clean it, about ready to turn it back on.
 
chrisasst said:
It is programmed correctly. It was working fine. Now all of a sudden today, after testing different LFF and heat #'s, it is not working. I turned the stove off at about 4 to clean it, about ready to turn it back on.


When you got through playing how did you get things back to the way they were?
 
stoveguy2esw said:
pdvc with a stat;
the stove when hooked to a stat will work in a "high/low" manner, meaning that when you run the stove and set the stat to a temp it will try to hold at that temp by cycling between the heat range you select on the board, and low or "1" though the numbers do not change on the board and the "blower speed is not affected.

so, the OP said he is running on heat range of 2 so what would happen is that when the setpoint on the stat was reached (the temp he picked on the stat) the stove would slow down the same as if the heat range was lowered to a "1" and continue to burn at that rate until the stat called for heat again, in which case it would revert back to heat range 2 that the OP was running on.

so, the stat could function normally and not show a major difference in output when it changes.

Mike,

I just installed a t-stat on my 25-PDVC yesterday. It was already warm in the house, so I didn't get a chance to see how it works when it cycles. Do I understand you correctly that the convection blower speed doesn't change, but only the pellet feed (top auger) is affected?

I have the feed and blower both set to 9.
 
fyrfyter4 said:
stoveguy2esw said:
pdvc with a stat;
the stove when hooked to a stat will work in a "high/low" manner, meaning that when you run the stove and set the stat to a temp it will try to hold at that temp by cycling between the heat range you select on the board, and low or "1" though the numbers do not change on the board and the "blower speed is not affected.

so, the OP said he is running on heat range of 2 so what would happen is that when the setpoint on the stat was reached (the temp he picked on the stat) the stove would slow down the same as if the heat range was lowered to a "1" and continue to burn at that rate until the stat called for heat again, in which case it would revert back to heat range 2 that the OP was running on.

so, the stat could function normally and not show a major difference in output when it changes.

Mike,

I just installed a t-stat on my 25-PDVC yesterday. It was already warm in the house, so I didn't get a chance to see how it works when it cycles. Do I understand you correctly that the convection blower speed doesn't change, but only the pellet feed (top auger) is affected?

I have the feed and blower both set to 9.

that is correct, the feed rate drops to low just as if you had lowered the heat range to 1, the blower speed is not affected
 
Ok, clearly my Tstat or something is not working. Refresh my memory, what ports in the Tstat do the wires go in. I have a Red and White wire. I put the white in the W spot and the red in the R1, which had a jumper in it. Is this correct. The Tstat is a honeywell rth6350
 
chrisasst said:
Ok, clearly my Tstat or something is not working. Refresh my memory, what ports in the Tstat do the wires go in. I have a Red and White wire. I put the white in the W spot and the red in the R1, which had a jumper in it. Is this correct. The Tstat is a honeywell rth6350

White in the W port and red in the R port which is jumpered to the Rc port.

Make certain that the setup is for heat only.

Also make certain your lff and lba are not set such as there is just a little difference between the #1 and #2 heat range settings.
 
Is the Jumper wire suppose to stay in there also or does that get removed completely?
Today I left the LFF at 7, LBA is at 5 and the heat # was at 3.
Wife called said the Tstat said it was 85 inside temp, and I have the Tstat set at 70.
 
chrisasst said:
Is the Jumper wire suppose to stay in there also or does that get removed completely?

The jumper can stay, but you have to be certain the t-stat is set for heat only otherwise it will call for heat when it would indicate cooling in a three wire White Red Red Cooling setup. You can also remove the jumper.
 
IDK, I think I threw away the box, need to call lowes and see if they will take it back with out it I guess.
 
Ok, maybe I can't use this tstat with a pellet stove. It gives system types and settings...
One option to set it at is : Heating only: gas, oil, or electric heating without central air conditioning. This should be the one correct?

Other options are Heating and cooling that uses central air or heat pump, or heating only with fan, cool only or heat / cool multiple stages..
 
chrisasst said:
Ok, clearly my Tstat or something is not working. Refresh my memory, what ports in the Tstat do the wires go in. I have a Red and White wire. I put the white in the W spot and the red in the R1, which had a jumper in it. Is this correct. The Tstat is a honeywell rth6350


hook one wire to "W" and the other to "G" doesnt matter which wire goes to which, the "R" is for gas if you have a "electric or heat pump"/"gas or oil" selector , set to electric or heat pump.
if you have a "fan" control set to "on"
 
That didn't work either. When the Stat is on, watching the flame, the stove goes high, then low ( more high than low) even though the actual temp is higher than the set temp. It even does it when the actual temp is lower than the set temp. If that make sense.

Here is a link to the manual. If someone has a minute to look it over, maybe you can tell me better what you think the settings should be on.
http://customer.honeywell.com/techlit/pdf/PackedLit/69-2416ES.pdf
http://customer.honeywell.com/techlit/pdf/PackedLit/69-2415ES.pdf



My wife through out my reciept apparently so I can't even back this back and get $ back.
 
Actually R and Rh are for heat and Rc is for cooling most t-stats come jumpered R or Rh to Rc.

The reason the little symbol comes on lower than the set point and goes out after the set point is reached is called swing or compensation. It allows a longer period of not calling for heat this would allow a pellet device to attain shutdown before firing up again, or for a heating system to not cycle a large number of times burning out motors or in a cooling system the compressors.

Some stats have compensation that works a slight bit differently where the stat stops calling for heat a certain temperature less than set point, this feature gets used on steam or hot water systems to stop temperature overshoot.
 
here is test to see if stat is "talking"to stove;

shut stove down
unplug stove
plug back in and quickly press LFF and AOT buttons (2 fingers) and release

if stat is calling for heat there will be a dash " - " in the blower speed window, if not it will be blank.

if dash is there , lower stat temp and see if it goes away, raise again and see if it comes back

if no dash turn up stat to call for heat and look for dash, then lower and see it goes away.


if this is happening the stat is working with the stove
 
stoveguy2esw said:
here is test to see if stat is "talking"to stove;

shut stove down
unplug stove
plug back in and quickly press LFF and AOT buttons (2 fingers) and release

if stat is calling for heat there will be a dash " - " in the blower speed window, if not it will be blank.

if dash is there , lower stat temp and see if it goes away, raise again and see if it comes back

if no dash turn up stat to call for heat and look for dash, then lower and see it goes away.


if this is happening the stat is working with the stove

So I did this, I changed the Tstat settings and the dash DID appear. The dash did disappear and reappear with the up and down of the Tstat. HOWEVER, something is just not right. I have the Tstat set at 73 an the actual temp is 77 and CLIMBING. I wish I had a video camera to show you what it is doing. The stove looks like it is dropping down to the lowest setting but then the flame grows big again. I have the bottom 3 set at 6-4-1 ( which is factory settings) and the heat and blower at 9-9 Just so I can distinguish the difference in flame. I just don't understand. I am seeing the dash, should be working but yet it is not.
I even hooked up the OLD Tstat I had that was working with the stove, and that is not working now either.
Anything else I can try? I am sure you think I am nuts, but
 
If the stove on low can raise the temperature it doesn't mean anything is wrong.

Put the setting you want the stove to go to when the stat is calling for heat to 1 do not screw with any other settings, tell us what happens.
 
What's the outside temperature? I know we're having an unusually warm winter with temps today in the 60s. My stove is also overshooting the t-stat, but it's because even the low burn is more than is needed to maintain the temperature in the house. Since I was out hunting all day and my wife was home with the kids, I left the stove going with the t-stat set to 68. When I came home for supper it was 76 inside and my wife had 2 windows open. The stove just can't put out any less heat unless I shut it down (or load it up with junk pellets).
 
SmokeyTheBear said:
If the stove on low can raise the temperature it doesn't mean anything is wrong.

Put the setting you want the stove to go to when the stat is calling for heat to 1 do not screw with any other settings, tell us what happens.


Ok, so I haven't touched the stoves setting or Tstat in two days. I had the stove set on 7-5-1 heat #2 and the Tstat has not worked. I come home today and changed my settings to 3-5-1 heat heat #9 and the tstat seems to be working. ( knock on wood)
 
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