Lear Siegler Wall Heater back clearance

Steve Burke · 09-18-2009, 05:29 PM

HVAC Experts,
I have a Lear Siegler G350SW80 wall heater in a duplex i recently bought. The unit sits in a 2x4 wall, but it appears that someone had cut (hacked) away the sheetrock/plaster on the non-heat side. Does anyone know if the clearance requirements for these old heaters and if it is possible to sheetrock the back?
Thanks!

Flashheatingand · 09-18-2009, 09:22 PM

You might check out the clearances from a Williams Wall Furnace site. They are a competitor, but their clearances are likely the same. At least you have a reference. Good luck

Steve Burke · 09-18-2009, 10:03 PM

Hey Flashheatingand,
thanks for the insight...here is the URL for others who may have the same question http://www.wfc-fc.com/pdf/Monterey_T...t_Brochure.pdf

bottom line is that it looks like i can hang sheetrock on the backside.
Thanks!

SKIP4661 · 09-19-2009, 04:36 PM

The drywall was probably removed in hopes of getting heat from the backside of the furnace.

Yoyizit · 09-19-2009, 05:22 PM

Gypsum, being inorganic, does not burn.

Paper yellows at 150C.
http://www.tcforensic.com.au/docs/article10.html

How long can you touch the backside of your heater after it's been on for a while?

no burn ever at 42°C(108°F)
burned in 30 sec at 54°C(129°F)
5 sec at 60°C(140°F)
1 sec at 71°C(160°F)