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JordanScott90

New Member
Mar 4, 2021
12
Winnipeg
Hello all

I am in the process of potentially swapping out my larger onyx with the pearl 3600 by rsf-icc. It mainly will come down to IF the heat dump will work or not. It would be ducted to the basement directly below for supplemental heating. If it doesn't work I will simply leave my current fireplace and just do a updated makeover. Now my onyx is around the vicinity of 41-1/2 inches wide and upon remembering the install of the unit, there was some room left on both sides, about 4-5 inches roughly. Now the pearl 3600 itself is 34-5/8's inches wide and is much smaller than the onyx giving more room on both sides. I added an image from when my current fireplace was installed for a visual idea. I am hoping someone here knows this type of stuff well, and could give me some insight if there is any way to make this work with very tight clearance space as my basement gets very cold, so this system would help me out greatly.

Thank you so much!

001.JPG
 
Last edited:

mcdougy

Minister of Fire
Apr 15, 2014
676
ontario
Is the current fireplace in a brick opening or a wood framed opening? It's kinda hard to tell from the pic you will need some "head" room as well as side room in my opinion. The folks at rsf should be able to help you with size requirements.
 

JordanScott90

New Member
Mar 4, 2021
12
Winnipeg
Hi thank you for you reply. It is not brick but wood framed with some sort of dry board finished all around. Problem is they won't know for sure until the stone is taken down and they can see in, and that's of course if i had bought the unit.
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,794
South Puget Sound, WA
Didn't the Onyx have a central heating ductable option? That seems like it would be a less disruptive and much lower cost. What is area is adjacent to the sides of the framing for the Onyx? Is this interior or exterior framing?
 

JordanScott90

New Member
Mar 4, 2021
12
Winnipeg
The chase is exterior to the house and the face of the fireplace is flush with the living room interior wall. There is a central heating option but due to the placement of the fireplace it would not work for us. The last ditch effort would be the heat dump installed with the pearl. I attached 3 more pictures that might give more of an idea as to the space I am working with.

20211012_184505.jpg 20211012_184331.jpg 20211012_184253.jpg
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,794
South Puget Sound, WA
Yes, that's very helpful. The nearby window reduces the option for expansion on that side.

Question: Even if the Onyx was replaced how would the hot air duct from the fireplace get into the basement when the fireplace is cantilevered outside of the foundation wall? Were the joists extended an addition 2'+ under the chase?
 

JordanScott90

New Member
Mar 4, 2021
12
Winnipeg
You have a good point there, I thought the joists had extended a bit under the chase just enough so that maybe they could angle it some how. But upon further investigation I did today, the fireplace does seem to sit too far from the basement ceiling. I just assumed maybe they could angle it through some how and it would just fit. The unit heats the upper two levels great, but the basement gets freezing in the winter.
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,794
South Puget Sound, WA
It sounds like there will need to be an independent heating source down there. Are the walls fully insulated?
 
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JordanScott90

New Member
Mar 4, 2021
12
Winnipeg
They are insulated, but regardless when the temps drop well below zero it loses warmth fast, and having a cement floor probably doesn't help either. I do have a furnace, but that only turns on at night for a short period of time once the fireplace dies down, or if we aren't burning at all.

But thank you for your insight on this, I may still downgrade to the pearl since the onyx is much too big for my house. It's an amazing fireplace, but extremely difficult to burn low on mild days.
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,794
South Puget Sound, WA
Have you looked into zoning the furnace with heating for the basement on it's own duct work and thermostat?
 
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JordanScott90

New Member
Mar 4, 2021
12
Winnipeg
There are two vents that vent directly into the basement, but are closed off to allow more heat into the upper levels when the fireplace isn't being used. I could open them again, but heating that area is harder than the upper levels because the space really doesn't hold heat well at all. But I'm sure I will figure something out, I will investigate your idea as well, Thanks!
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,794
South Puget Sound, WA
To zone it off it would take a new, larger duct or at least a large grille on the main trunk duct that is motorized and on a thermostat. When it calls for heat the large basement grille opens up and dumps the heat into the basement. The grille closes once the call for heat has been satisfied.