couldn't answer this cat question

[d.n.f.]

Hey:

I am new and would like to say this is an amazing site...

I am stoveless but did have a Hearthstone cat stove which I liked. Anyway, my friend is buying a stove and had this cat question which I couldn't answer. Load the stove up and go to bed and leave the cat on right? Wake up the next morning and maybe have some coals left, reload the stove and turn cat off. So since the temp fell during the night below cat engagement temp, why not leave the cat on all the time, so once it gets to temp it engages?

I said you can't do that, but the couldn't give a snappy response to it other than it will smoke and not burn properly However, what is happening at 4am when I am sleeping with the cat on and the stove hovering at 200F????

Any help (more for my own sake) would be appreciated.

In the market for a stove but methinks the wife wants a built in RSF. Yech. Worried we won't get the heat output and the initial cost is almost double. Not the primary heating unit. They look nice but the cost is crazy. Don't know if I can get any other products (Kozyheat ex) cause I am in BC.


cheers

 

[TMonter]

If you leave the cat on because the cat reduces flow (pressure drop) the stove will not heat up quickly and will smoke for a lot longer than disengaging the cat and allowing it to quickly get up to temperature. Under some conditions you could also plug the cat although this is less likely.

Mainly disengaging the cat when loading allows the stove to get back to light off temperature faster and hence for the user to burn with less overall emissions.

 

[hookspacken]

If I dont dis-engage the Cat when loading or starting a fire, it wont get enough air and will just smolder, fill up with smoke and eventually start pouring smoke out the air inlets, I am sure. Engaging the Cat drasticly reduces the pull of the draft, slowing down the burn. At least in my stove...

 

[d.n.f.]

yeah I get that point, but what about the reverse as the stove cools down? Why doesn't it do this when the stove temp is 100 degrees F?

 

[begreen]

Because at that point there is no more smoke or gases left in the coals. This is the opposite of when fresh wood is added.

 

[Jags]

Because at that point there is no more smoke or gases left in the coals. This is the opposite of when fresh wood is added.

Yep, what BG said.

Basically, all the volatile "nasties" that the cat feeds on are gone by the coaling (and cooling) stage of the fire.

 

[Todd]

Putting in a fresh load of wood into the stove without bypassing the cat could cause thermal shock and crack the combustor. There is always some moisture in your firewood and you need to bypass the cat for 10-15 minutes to get that moisture out. Your stove top may be 200 degrees, but the cat may still be 400-500 or more. Fresh wood will send a relatively cold steam through it that the ceramics don't like.

 

[d.n.f.]

Thanks so much.

Now I will sound intelergent!