The vac switch is a safety feature. It shuts down power to auger if there is no vacuum present in firebox. This can happen from an assortment of issues. You could have a blocked vac hose. You could have a blocked nipple that the vac hose attaches to. You could have a blocked exhaust, or a bad door gasket. If the door glass breaks, it will shut down the feed. And as Ssyko mentioned above with the comb. blower. Checking all these things could save you the price of a new vac switch, if it is not the problem. kap
Alright, I give in..
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Alright, I will check that nipple to make sure it is clear,,, I will try the vacuum switch again,,,, if it still fails then I will know that is the problem......right?
My exhaust is open and clear,,,,,checked that... the door gasket is nice and tight.
After studying the owners manual and watching the ‘dealers’ video,, I find that the vacuum switch has 2 purposes:
1. To shut the feed down if the fire goes out and the fire pot fills up with unburied pellets......
2. To shut the feed down if the door is opened during ‘burn’ time. Well, I certainly am never going to open the door while there is a nice fire roaring away in there.
I’m not sure if the vacuum switch is the main culprit, however, after jumping it,,, sure seems like it....I have been blaming the problem on the thermocouple, which I did replace.
It seems to me that the vacuum switch is sorta a ‘idiot’ switch. In a way . It’s not too much money to buy a new one and hook it up,,,, if the current one is truly gone.....will check that nipple again to be sure.
Perhaps I mis-understood what the ‘dealers’ video said about the vacuum switch, it does seem that if the stove is kept clean and in good repair,,,, Well, if the fire pot fills up with pellets it’s going to stop burning,,,,,, And I’m not going to open the door while the pot is burning good and strong,,, no need to..... so it seems I am missing something.
Please help me out with this.
1. To shut the feed down if the fire goes out and the fire pot fills up with unburied pellets......
2. To shut the feed down if the door is opened during ‘burn’ time. Well, I certainly am never going to open the door while there is a nice fire roaring away in there.
I’m not sure if the vacuum switch is the main culprit, however, after jumping it,,, sure seems like it....I have been blaming the problem on the thermocouple, which I did replace.
It seems to me that the vacuum switch is sorta a ‘idiot’ switch. In a way . It’s not too much money to buy a new one and hook it up,,,, if the current one is truly gone.....will check that nipple again to be sure.
Perhaps I mis-understood what the ‘dealers’ video said about the vacuum switch, it does seem that if the stove is kept clean and in good repair,,,, Well, if the fire pot fills up with pellets it’s going to stop burning,,,,,, And I’m not going to open the door while the pot is burning good and strong,,, no need to..... so it seems I am missing something.
Please help me out with this.
Ssyko
Minister of Fire
I just rebuilt a whitfield profile 20 that had a hopper fire due to a bypassed vac switch and it got so hot it melted the control board that is mounted on the side of the stove. combustion blower seized and auger kept feeding pellets it went up the tube and cooked. house was full of smoke. so if you feel its an idiot switch, leave it the way you have it and press on.
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Ssyko,,,,thank you for your information,,,, I will get a new switch if necessary, however this stove is 27 yrs old,,, and I ‘m not sure if it is the original switch,,,,,, back in the day lot’s of things were done to satisfy the ‘liability; concerns,,, on stoves, cars,,, everything... I’m just trying to understand the logic.
Umm,,, how many hopper fires have you had??
I know the guy who rebuilt my stove years ago,,, had mentioned there could have been a fire in the feed chute,,, wasnt sure,,,,however, that would have been in the old, original configuration
I’m still learning.
Ssyko
Minister of Fire
I’ve only done the one. I didn’t have the fire myself, i bought it to rebuild and sell. I really don’t care about the manufacturers liability it is still a good safety feature. I would rather buy a $50 switch than lose someone ora home. Every stove i sold is factory oem parts and works as designed. I sleep well at night
$46 is pricey for a vacuum switch, if you know the range of the switch, you can use any vacuum switch with the same values, check with Grainger and see what switches they have to meet your needs, you can usually find one for around $12 dollars. It doesn't have to be Grainger, any HVAC supply will have them, just let them know the range, which is often times on the switch.. You may have to find an alternate mounting method, but more often than not the mounting is even the same, remember a vacuum switch is a vacuum switch so long as its the same range, used quite a bit in the HVAC industry, so quality parts are available for much less than the stove manufacturers OEM part.
As others have said, I wouldn't run it without one installed, especially if you leave it unattended for any amount of time!
As others have said, I wouldn't run it without one installed, especially if you leave it unattended for any amount of time!
Thank you Nitro...that $46 was for a whole kit, tube, mounting things,,, instructions....
However, I like your advice very much,,,,I’ll be off to my furnace man tomorrow,,, if we don’t get the blizzard they are promising,, and see if he has the right switch,, or will order from Grainger....Thanks again.
Mt Bob
Minister of Fire
I will agree,the vac. switch is a very important safety device.Many newer stoves still use them,although a manual reset snap switch mounted to the auger chute has been used by some stove manufacturers.Still a lot of those old quads out there running.
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Take these numbers to your HVAC guy,the switch does not have to be exact,as long as the opening reading is the same.You may have to use a plastic automotive adapter,to fit 2 different size hoses,to make a different switch work.
Thanks, Bob, for the details.....I’ll be off to my HVAC as soon as the blizzard stops,,,will also look online.
Mt Bob
Minister of Fire
Got a new vacuum switch, installed it, and everything works fine, so it looks like this Old Quad is good for a few more years.
Thanks for all the help and patience.
A question: My pellets don’t slide down the sides of the hopper easily,,,,,should I just clean the sides(walls) and put a coat of wax on them so the pellets slide easier...??
Thanks for all the help and patience.
A question: My pellets don’t slide down the sides of the hopper easily,,,,,should I just clean the sides(walls) and put a coat of wax on them so the pellets slide easier...??
Ssyko
Minister of Fire
Mt Bob
Minister of Fire
LOL.I have always used spray on graphite,or such,but,the hot ticket lately seems to be to line the hopper with the high temp metal "duct" tape( Tape for actual duct work,available at most hardware stores),I have seen so many good reports of this,will be doing it on one of my stoves,later on.
Thanks Bob,,, I will give that a try,,, cause waxing it didn’t help much the last time.
Ssyko
Minister of Fire
I got a b new vac switch and stove is working fine, However, I noticed the old vac switch was .02 inches water column..I don’t know what the difference means,,,,,
DneprDave
Minister of Fire
The difference is .03 inches of water!
Thanks, Dave,,, I think I need something more accurate than that.....................lol
Ssyko
Minister of Fire
I believe the pic Bob posted was out of the owners/tech manual. I don't know what to tell you. higher wc would just cut out sooner if there was a combustion failure.
It’s ‘supposed’ to cut out if the door is opened while burning,,, doesn’t seem to do that, but I only tried it once, so it really isn’t a concern,,,, and it may not do it on an older model....In the dealer video they mention that on one side of the burn pot, and the other side,, that the vacuum is ‘slightly’ negative or ‘slightly’ positive. Not sure what they mean by ‘slightly’ but my stove is working fine,
Mt Bob
Minister of Fire
The pic I posted was from a new switch,from a parts place.Your stove is a bit of a strange duck,it has a blower to blow air into the firebox,in addition to the main exhaust fan,which creates the negative pressure.I think they did this for faster ignition,back in the day.As long as you have a functioning switch in place,I would not lose any sleep over it.
Thanks Bob,,, my stove is running fine now... I know it has some unusual features, for example, to empty the firebox. There is a lever that goes out to the left side and when pulled opens a gate on the bottom of the firepot and lets the clinkers fall out.. I like that feature,,, Now when I start it, there is flame, (pellets burning brightly) in less than 3 minutes.
And of course, it is thermostat friendly,, was designed that way,,,,
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