One heat exchange flue not blowing

[Coltontvb]

I'm unsure where to start, but this is my first post on the forum because I am simply dumbfounded and have no where else to look. I have a quadra-fire contour that I have been running for 12 years with no troubles. I meticulously clean it weekly and maintain anything that goes wrong as soon as possible, but this is a problem I had yet to see until now.
I recently had issues with a lazy flame and the stove was burning the pellets quite poor, I turned off my stove and replaced the door seal + the pot seal, and also changed the switch #2 (for the air movement blower motor, not the convection blower) because I had it jumped to run all the time as it had failed and I was waiting for my new switch, which did indeed repair the problems. While I was piddling around I decided to replace my blower motor because it was noisy...efficient but noisy. I removed it and cleaned out all the dust and what not that had accumulated since the start of the cold season, installed the new one and waited for it to turn on. The blower turned on but something odd occurred to me, one of the heat exchanger flutes puts out little to no heat, while the one beside it doesn't blow at all!
I didn't notice it before I installed the blower, but maybe this has been happening for a while, is it possible something somehow got into one of the flutes ie: a mouse, and if so why would heat be minimal from only one of the other flutes that is beside it?
I tried to flash a light through the flue that isnt working but i cant see any light passing through it, I also don't have a compressor or anything of the sorts to blow air backward through the inoperative flue. As I said I am meticulous about cleaning my stove and though it is mid season the exchanger is still very clean. The inoperative ones are no more dirty than any of the others.

 

[kappel15]

Welcome to the forum. The convection blower is the one that blows the hot air into the room. The combustion blower is the one that blows the exhaust out the pipe. Sounds like there has to be something inside the heat exchanger tubes. But, there will be less air on the outside tubes, compared to the inside ones. Best thing to do is pull the convection fan(one that blows air into room), and try to work from either end, to see if there is any obstruction n the tubes. From underside, maybe something flexible, and from the topside, something solid. Did you replace both blowers, or just one? If you replaced the conv. blower, did you get it seated properly in position? kap

 

[zrock]

go to the store and grab yourself a bottle brush and use it and run it down the tubes. They are only a few $$ and if something is plugging it it should clean it out. It may just be a buildup of dust over the years and when you tore it down it got a blast of more dust and plugged up

 

[Coltontvb]

It was the convection blower, sorry for the misuse of the word. The new blower is definitely seated properly, it only goes in one way, time to fish out some stuff from the tubes. Ill let you know what if my problem gets fixed

 

[Coltontvb]

Well I have run a brush down there and I have been unsuccessful in removing anything from there, but the brush does come out the bottom where the convection blower is...I'm at a loss.

 

[kappel15]

Is it a factory blower you installed? Some of these after market ones they sell as factory, leave a lot to be desired. And looking at your original post, it had to be the #1 snap disc you replaced for the convection fan. Just to keep the record straight. kap

 

[Coltontvb]

You are correct it was #1, either way and beyond the point is that I have amazing air movement out of all the heat exchanger pipes but 1 or a couple (hard to tell as they all blow on an angle) Also I have tried two blowers, as the first they sent was noisy both had the same effect

 

[Ssyko]

Like Kap said if the blower was not a True OEM it may not put out as much air as the original. Which could leave the pathway to the exchanger tubes not pressurised as it should be, leaving you with lower output in all the tubes.

 

[Coltontvb]

I understand that, but my situation is that only ONE tube has no air movement and the other two beside are blowing room temperature air with very GOOD pressure as with all the other tubes, which I find unusual. I have cleaned and spun all my tubes, and fed a brush all the way through the ones that are in question.

 

[Ssyko]

Ok, well the center tubes will collect more heat than the out ones just because they are in a more direct line of the fire and we will say the blower is moving the correct amount of air. The air will move in the least amount of resistance and the fans are blowing up a tapered duct to the exchanger tubes they will blow in a straight path. So there may be a tube or 2 that isn't as hot or seams to not have airflow. Only real way to find out is to put a flow meter on each tube and see what the readings are at.

 

[Coltontvb]

One is dead out, there is an obvious dead tube, i'm going to say something is in the ducting that is affecting the flow but the disassembly of the stove to get to the ducting is just not worth it, the stove is almost 12 years old now, and the problems are just accumulating. The more aftermarket parts that go into the stove and the more disassembly that occurs just worsens the condition of the stove. IE: there are multiple rivnuts that have failed and just spin, the stove rattles and clinks because panels are breaking at weld joints etc. Anybody have any recommendations for stoves....

 

[zrock]

As ssyko is explaining if the fan output is lower than oem and even if the fan blades are a degree different in design the air movement will take the path of least resistance. you can have a tube side by side and one will get full air flow where the other will get nothing. You said you didn't notice before but have you ever checked? Since you had issues with your stove and replaced some parts you may now but be nit picking and looking for issues? Iv done the same thing and pulled my hair out for nothing..LOL
I have different stove not sure if everything is OEM in it or not but my heat exchange blows strong in the middle and gets weaker and cooler towards the outside. Since i got this stove used i figure thats the way it is and live with it since the stove heats my home quite well

 

[Coltontvb]

I never noticed it prior but again I wasn't always checking the airflow, maybe I am just pulling my hair out for nothing. It does keep my house warm so what else could I ask for lol. My convection fan actually quit the other day, I made another thread on here but there hasn't been an answer. Pretty sure the control box bit the dust, no power going to the snap disc...I just can't win this winter

 

[kappel15]

Fuse, wire harness, or control box. Depends on what all is not running. kap

 

[Coltontvb]

Only the convection blower wont run, tested the wire for a voltage drop/open and it tests okay. According to the wiring diagram the only two fuses are the circuit board fuse (which makes nothing turn on) and the large wiring harness fuse which is also okay and causes nothing to run when open

 

[kappel15]

I was just reading your post. It eliminates fan and wire harness and fuses. Only leaves control box. Best way to test is if you know someone with a Quad stove you can test your box in, or a dealer that can test it in a stove for you. And always remember to unplug stove, before removing or installing a control box, or you run the risk of toasting it. kap

 

[Coltontvb]

Cool, thanks a bunch guys. Found a new used box itll be two weeks of electric heat I guess. I might just wire up a rheostat switch to outlet power and run it manually for now. Sadly I cant test it as I live in a pretty remote location.

 

[kappel15]

I would run it manually also. No sense paying the electric company all that money. kap

 

[gfreek]

Cool, thanks a bunch guys. Found a new used box itll be two weeks of electric heat I guess. I might just wire up a rheostat switch to outlet power and run it manually for now. Sadly I cant test it as I live in a pretty remote location.

Running it manually via a rheostat is not a bad idea. I did that with my Harman when the board quit..