Buck 3-speed thermostat vs. Rheostat. need help!

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lewishw

New Member
Hearth Supporter
Nov 24, 2009
1
Colorado
Hi all,

I have an old regular buck (model 26000 i think) that has a finicky thermostat. In the "automatic" mode, after a fire has been burning for a few hours the blower cycles on for just a few seconds, and then makes a hissing noise like it is trying to slow itself down electrically or something. When I flip the switch to manual, it runs just fine constantly. I am thinking it is a bad thermostat.

My question is this: Should I just replace the 3 speed thermostat since the motor seems to still be fine, or just take the leap and replace the motor with the single speed model and do the rheostat setup? Has anyone had experiences with this setup? Which one seems to work better overall? Any input would really help.

Thanks everyone

Hunter
 
I took this off Bucks web site in the FAQ section. I'm not sure if it is exactly what you have or not but it does sound like it. If it is I do recommend updating it.


I have an old double door wood stove with a 3-speed thermostat (CPI bar). It only works on high. What is needed to make it 3 speeds again?
The CPI bar is no longer available. You will need to replace your CPI bar with a CPI replacement kit, which consists of a thermostat disc, rheostat, rheostat knob, and the wiring schematic. This replacement kit is variable speed (not 3 speed like the older CPI bar) and is adjusted with the rheostat knob. Order part # MA 100120.
 
My son and I both have Bucks. His thermostat went bad and he went the rheostat route - hates it. Buck doesn't have the 3 speed anymore but this site does - (broken link removed). There are others but can't find them right now.
 
Does this unit have a 3 speed fan switch as well as a 3 position switch (auto/manual/off)? I'm not familiar with the controls on this unit, but from the description it sounds like the snap switch may be failing. The snap switch is a thermal sensor and is what switches the fan on/off depending on temperature. That is the part I would replace first.
 
BeGreen said:
Does this unit have a 3 speed fan switch as well as a 3 position switch (auto/manual/off)? I'm not familiar with the controls on this unit, but from the description it sounds like the snap switch may be failing. The snap switch is a thermal sensor and is what switches the fan on/off depending on temperature. That is the part I would replace first.
I have had this same stove for over 25 years. What it has is a 2 position switch, manual (High) and automatic. The motor has 3 wires, 3 speeds. The thermostat sends power to the 3 speeds, first temp - low, next higher temp - medium, highest temp - high. Buck called the thermostat unit a CPI bar, whatever that stands for. This site (broken link removed) , sells a replacement that consists of 3 thermo discs. Here is the wiring diagram. The CPI unit does have snap switches and they do fail and cannot be replaced. The site above solves that problem.
 

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You can find the individual thermostats and anything you might need for the Buck here: (broken link removed to http://www.stovepartsunlimited.com/pricing/pdfs/2008_parts_pricing_retail_rev_09_02_2008.pdf)

Mine is doing the same thing, how did you fix yours?
 
My Buck stove just had the fan motor go out. It had a toggle switch which was either on automatic (it kicked on at a certain temperature), or manual (on all the time). When it went out I went to the local wood stove dealership where Bucks are sold and bought the new motor, thermostat, and variable speed fan knob. I installed it. It works fine. Except for one thing. Working at the highest speed possible, the fan probably moves 2/3 as much air as the previous motor and switch. It probably moves half as much air as my 3 speed fan and switch I had on my Little Buck in my basement. Bottom line: I hate this thing because it can't keep the stove cooled down enough or push enough heat into the house. I would STRONGLY recommend NOT getting the standard buck replacement for the 3 speed fan.
 
sunshineband said:
My Buck stove just had the fan motor go out. It had a toggle switch which was either on automatic (it kicked on at a certain temperature), or manual (on all the time). When it went out I went to the local wood stove dealership where Bucks are sold and bought the new motor, thermostat, and variable speed fan knob. I installed it. It works fine. Except for one thing. Working at the highest speed possible, the fan probably moves 2/3 as much air as the previous motor and switch. It probably moves half as much air as my 3 speed fan and switch I had on my Little Buck in my basement. Bottom line: I hate this thing because it can't keep the stove cooled down enough or push enough heat into the house. I would STRONGLY recommend NOT getting the standard buck replacement for the 3 speed fan.
That is exactly what my son found. He has since replaced the rheostat with the 3 thermo disc unit and 2 position switch (auto and manual[high]) from the site in my previous post above, and the stove works great again. Solves the problems you are having completely. I don't know what motor buck is selling now, but you do need the 3 speed, which the site in my previous post sells. I have ordered several items from them and their service is excellent. You do have to call the 800 number to order (I talk to Terry).
 
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