Rich Burning STERLING Ht Model 8532, How Tell if Setup for NG or LP?

[KenO]

Am looking at a house that has a STERLING Ht Model 8532 Gas-Fired Direct Vent Heater that is burning too rich (black soot on inside of stove glass and above the side vent).
Read the Owner’s Manual & Installation Guide (broken link removed to http://www.hearthstonestoves.com/assets/files/document_library/Sterling-Ht8532Manual.pdf) and noticed on p22 "All Sterling stoves are set up for use with Natural Gas when built. However, these units are easily converted for use with LP, and visa versa."
The Rich Burning Sterling-Ht 8532 uses LP.
How can I tell if the STERLING Ht Model 8532 was converted to LP or if it is still setup for Natural
Gas?
Appreciate any tips or suggestions!
Thanks
Ken

 

[DAKSY]

Am looking at a house that has a STERLING Ht Model 8532 Gas-Fired Direct Vent Heater that is burning too rich (black soot on inside of stove glass and above the side vent).
Read the Owner’s Manual & Installation Guide (broken link removed to http://www.hearthstonestoves.com/assets/files/document_library/Sterling-Ht8532Manual.pdf) and noticed on p22 "All Sterling stoves are set up for use with Natural Gas when built. However, these units are easily converted for use with LP, and visa versa."
The Rich Burning Sterling-Ht 8532 uses LP.
How can I tell if the STERLING Ht Model 8532 was converted to LP or if it is still setup for Natural
Gas?
Appreciate any tips or suggestions!
Thanks
Ken

There are a MINIMUM of 5 steps to doing an NG to LP conversion.
1. The regulator head must be changed to an LP version.
2. The Burner Orifice must be changed to the specified size for LP.
3. The Pilot Orifice must be changed to the specified size for LP.
4. The air shutter on the burn tube should be opened all the way & (MAYBE)
adjusted back to get the correct flame presentation.
5. A sticker indicating that the control has been converted to a different fuel
should be applied to the valve, the rating plate & the back of the unit, along with
the initials of the NFPI Certified gas technician who did the conversion.

That being said, open the air shutter all the way & that baby will burn nicely. Those Hearthstone Sterlings are nice units...

 

[KenO]

DAKSY,

Question concerning "That being said, open the air shutter all the way & that baby will burn nicely. Those Hearthstone Sterlings are nice units..."

Do you mean even if the stove is operating on LP but still has the NG parts that it is possible to achieve correct Air Fuel ratio by opening the shutter?

Thanks for your help.

Ken

 

[KenO]

DAKSY,

I am ready to try opening the air shutters.

Reread the manual p20 "The air shutter is adjustable while the stove is burning. The two air shutters on the ember burner are adjustable. The right one (while facing the front of the stove) is for the low burn portion of the ember burner and the left one (while facing the front of the stove) is for the high burn portion of the ember burner."

Question: I did not see any mention of what order to adjust the two air shutters?

Do you have any suggestions or tips adjusting the two air shutters ?

Thanks again for your help!

Ken

 

[DAKSY]

Do you mean even if the stove is operating on LP but still has the NG parts that it is possible to achieve correct Air Fuel ratio by opening the shutter?

No, that probably won't happen. If you are burning LP through an NG unit, it will scare the crap out of you. Pilot flame will be more than an inch tall. The burner flames will be WAY TOO big. You will shut it down IMMEDIATELY when you see them (if you're smart). If you don't shut it down, we may never hear from you again...

 

[DAKSY]

DAKSY,

I am ready to try opening the air shutters.

Reread the manual p20 "The air shutter is adjustable while the stove is burning. The two air shutters on the ember burner are adjustable. The right one (while facing the front of the stove) is for the low burn portion of the ember burner and the left one (while facing the front of the stove) is for the high burn portion of the ember burner."

Question: I did not see any mention of what order to adjust the two air shutters?

Do you have any suggestions or tips adjusting the two air shutters ?

Thanks again for your help!

Ken

If you are burning LP, I would just open both all the way & forget about them - unless there are only blue flames in the fire box. If that's the case, close them slowly until the flames are bright yellow at the top with just a hint of blue at the burner ports. Turn the regulator knob (Hi-Lo) to low & adjust the right side shutter. Then, turn the regulator knob to high & adjust the left side shutter. You should be good to go.

 

[KenO]

"If you are burning LP, I would just open both all the way & forget about them - unless there are only blue flames in the fire box. If that's the case, close them slowly until the flames are bright yellow at the top with just a hint of blue at the burner ports. Turn the regulator knob (Hi-Lo) to low & adjust the right side shutter. Then, turn the regulator knob to high & adjust the left side shutter."

Thanks for the detailed instructions!

Checked the air shutters.
1. The right air shutter was almost fully open and moved it to fully open.

2. The left air shutter was almost fully closed and tried to move it to fully open but would not budge even when applied much more force than I used to move the right air shutter fully open so decided to stop before breaking anything.

Did a forum search using "unable to open air shutters" but only got "No Results Found".

Have you ever had this problem? Any ideas what is causing this problem and suggestions how to free up the left air shutter?

Thanks again for your help!

Ken

 

[DAKSY]

Checked the air shutters.
1. The right air shutter was almost fully open and moved it to fully open.

That shutter probably wasn't causing the sooting.

2. The left air shutter was almost fully closed and tried to move it to fully open but would not budge even when applied much more force than I used to move the right air shutter fully open so decided to stop before breaking anything.
Did a forum search using "unable to open air shutters" but only got "No Results Found".

Have you ever had this problem? Any ideas what is causing this problem and suggestions how to free up the left air shutter?

If you can't open the shutter, something is restricting its movement. You will have to get inside the firebox until you can see the shutter location to see what that restriction is caused by. This may require removing the burner...The ONE time I encountered that issue & it was caused by a jar of touch up enamel that had fallen down inside the unit during shipment

Thanks again for your help!

Ken

 

[KenO]

"If you can't open the shutter, something is restricting its movement. You will have to get inside the firebox until you can see the shutter location to see what that restriction is caused by. This may require removing the burner."

Any suggestions?

Thanks

Ken

 

[DAKSY]

"If you can't open the shutter, something is restricting its movement. You will have to get inside the firebox until you can see the shutter location to see what that restriction is caused by. This may require removing the burner."
Any suggestions?

It's been a while since I worked on one of these & I can't open certain .pdf files from this computer. That means that I can't open the manual you originally posted. I can't open the one from the Hearthstone web site either, so there's no way for me to tell you exactly how to remove the burner in order to see what the obstruction might be. Generally, there are 4 or 6 screws holding the burners in place, but like I said, unless I can see it, I can't be sure.

 

[KenO]

Following your instructions "Turn the regulator knob (Hi-Lo) to low & adjust the right side shutter."went to adjust the Manual Hi-Lo Pressure Regulator using the Valve Description diagram p16 as a reference but when looked carefully noticed that this stove is different. Instead of an extension rod extending from #2 (as it does for the gas cock #1) it has a red cap and the extension rod for Hi-Lo comes from the right side of the valve. Please check attached photo.

Thanks again for all your help!

Ken

 

[DAKSY]

Is that the extension rod coming off the valve directly above the red cap?

 

[KenO]

" I can't open certain .pdf files from this computer."

Do not know if it makes any difference because I have rechecked the man a number of times and have not found any mention of removing the burners

Ken

 

[KenO]

"Is that the extension rod coming off the valve directly above the red cap?"

Correct

Ken

 

[DAKSY]

" I can't open certain .pdf files from this computer."

Do not know if it makes any difference because I have rechecked the man a number of times and have not found any mention of removing the burners

Ken

And you won't ...You will have to figure it out by trial & error. Like I said, there are only a couple of screws holding it in place. Once you remove them & pull the burner, you'll be able to check for & clear the obstruction. You just have to make you replace everything the way it was. I just checked the Hearthstone site & there are no "Burner removal" instructions...

 

[KenO]

"Is that the extension rod coming off the valve directly above the red cap?"

Should have mentioned the other extension rod (above and left of the red cap is #1 Off, Pilot, On)

Ken

 

[DAKSY]

"Is that the extension rod coming off the valve directly above the red cap?"

Should have mentioned the other extension rod (above and left of the red cap is #1 Off, Pilot, On)

Ken

So that's where you will have to make the adjustment to set the air shutters - ONCE you figure out why the left side shutter doesn't function

 

[KenO]

Maybe this photo is better

Ken

 

[KenO]

Bob,

Am mentioning man info incase you are able to open the man pdf.

Reread p20 Detail A, "HI TURNDOWN KNOB PUSH DOWN AND TURN CLOCKWISE FROM (-) TO (+) FOR CONTROL OF HI FLAME.

Got idea that the red slotted cap may be a covering for the Lo Flame?

What do you think?

Tried to adjust and found could only turn counterclockwise, then realized it is a cap for the adjustment under it(white slotted).

2 photos

Ken

 

[DAKSY]

Bob,

Am mentioning man info incase you are able to open the man pdf.

Reread p20 Detail A, "HI TURNDOWN KNOB PUSH DOWN AND TURN CLOCKWISE FROM (-) TO (+) FOR CONTROL OF HI FLAME.

Got idea that the red slotted cap may be a covering for the Lo Flame?

What do you think?

Ken

No. Looks to me when you turn down the HI flame, then you will be at the LO flame position...

 

[KenO]

Question: From your experience, what do you think the adjustment under the Red Cover in photos I uploaded does?

Thanks again for all your help!

Ken

 

[DAKSY]

Not Sure, Ken. This looks like an older Robert Shaw EPU valve & there aren't a whole lot of them still in service. In fact, I didn't work on too many of them when I was a service tech...Somebody else will hafta chime in on this one.

 

[KenO]

"... This looks like an older Robert Shaw EPU valve & there aren't a whole lot of them still in service. In fact, I didn't work on too many of them..."

At least you know the name.

Any comments on what the common problems were with Robert Shaw EPU valves?

Also what did you replace them with?

Ken

 

[DAKSY]

"... This looks like an older Robert Shaw EPU valve & there aren't a whole lot of them still in service. In fact, I didn't work on too many of them..."

At least you know the name.

Any comments on what the common problems were with Robert Shaw EPU valves?

Also what did you replace them with?

Ken

They were upgraded by the manufacturers with the next generation of the Robert Shaw Valve...

 

[KenO]

Bob,

Do you have any suggestions how to find out what gas valves were used in the STERLING Ht Model 8532 stoves?

Thanks

Ken