Modine or Southern Burner Heater?

[Gin]

My ancient heater had to be replaced been looking at the Modine Hot Dawg and the So. burner 30,000 BtU . Green house is 12 by 24 pretty tight in Mo. think zone 7 ? What ever I get has to be vented had to get an un-vented in town( emergency) don't like it, lots of bud blast even with added air (No gas leaks in the line ) but can smell the LP when it turns off and on . What are your thoughts Thanks

[pavel]

Can't help you there, Gin, but wanted to say "Howdy, stranger!". Haven't seen you in "forever".

[Gin]

Hi , My friend

[Michael Saar]

The vented Southern Burner is 25,000 Btu; is this enough to replace your old heater?
How is your power reliability? The Southern will operate w/o electricity, the Modine won't.
The Modine is higher efficiency (80%); the Southern (vented) is probably about 70% efficient.
Are you using LP gas?
If one Southern Burner is not enough, one Modine may be less expensive than two Southern Burners.
More questions than answers, but questions you need to answer to make a decision.

[Gin]

Thanks for the info. Michael yes 25,000 Btu would be enough . I have almost decided on that one ,sometimes we have a power failure usually in the middle of the night I have been digging around on the internet trying to find out if the So. burner has a built in blower or if it has to be added separate . Thanks for your feed back it is appreciated ..

[Michael Saar]

As far as I know, the Southern burners all operate by convection. You will have to provide external air circulation.

[Gin]

You are right no internal blower on the So. burner . Thanks so much for the Info.

[eircsmith]

A vented heater mostly causes problems like incomplete combustion of fuel; which can lead to the creation of exhaust chemicals that in-turn can cause bud blast and even kill your orchids. I have heard only good things about the Southern Burner, but most of the people still go for a vented heater.

[raybark]

I have long been an advocate of separated combustion heaters, as they draw in outside air for combustion, then vent it again, so they don't draw the heat and humidity up the flue like most vented heaters. However, mine failed this winter, and not having the time to fix it, I went to my local home store and bought a Procom non-vented, wall-mounted, blue flame heater as a stop-gap measure.


It is very efficient, requires no power to operate, and I have seen no issues with bud blast or anything else that could be caused by incomplete combustion. The circulation fans that I run in the greenhouse 24/7 do a fine job of distributing the heat.

[Michael Saar]

The culprit is generally ethylene, caused by incomplete combustion of LP gas. My PhD chemist friend has assured me that natural gas (methane) cannot generate ethylene. I operated an unvented natural gas heater for years without problems; I would not use an unvented LP gas heater.