Propane heater/regulator help

[4spdragtop]

Im trying to figure out what psi or inches of water column my regulator is spec'd at. Im installing(just the grunt work) a 45,000 btu Big Maxx heater. Its a propane unit and I am almost at the point to call the furnace guy in to hook up. The specs in the manual says that I need 13" of water column, which I believe translates to 7-10 psi. I have a Marshall Brass Co. regulator, model #230. Does anyone one know what the specs are on the regulator??

Thanks
4spdragtop

 

[67Dart273]

13" of water is NO WHERE NEAR 7-10 psi. More on the order of 1/2 psi. That is a common figure for INPUT to the (built in) regulator of LP gas appliances. If the regulator came with it, and the thing is already "built" and the label is speced for LP (rather than natural gas) then you should be all set.

Normally you have one regulator right at the tank (may be supplied by the tank people) which drops the tank pressure (varies) down to 11-13" water, and the "in appliance" combination valve/ regulator then drops that down to whatever the manifold wants---used to be 7" for atmospheric burners. Newer power burners may vary, and should be ON THE LABEL


What sort of burner is this? Isn't there a spec for "manifold pressure" which would be with the burner fired, downstream of the regulator?

 

[daredevil]

may need to put a tee in the line and hook a manometer to it. It is probably calling out the supply pressure it needs maintained to operate correctly.This would be the pressure it has to keep while the burner is at full flame.

 

[4spdragtop]

Thanks guys, just got off the phone with the tech dept for Mr Heater. Mine is a Big Maxx 45k btu. Tech on the phone told me just what you said 67dart273, I need a low psi regulator....1/2 psi which is between 11-14" of water column and it has to be rated higher than the furnace btu. How can I tell what my reg is good for??

 

[4spdragtop]

As funny as it sounds, my bbq regulator will work. It accepts 250 psi and the outlet is 11" of water column. I guess thats because bbq's now a days pump out more btu's than my furnace LOL.

THANKS!!
4SPDRAGTOP

 

[67Dart273]

How can I tell what my reg is good for??

I'm not at all familiar with that regulator from your description. You might try to look up the numbers on it. Is it designed for use on a tank? If so, it is likely that it's just what you need..

except....

it's not just pressure, you need a reg. that can handle the volume. A little bitty regulator designed for something like a BBQ may not flow enough volume to maintain pressure.

Some idea of regulator capacity can be had by the outlet size---if it's 1/2 pipe or larger, it's propably large enough capacity.

Is it marked, anywhere, for LP? Generally, the difference between an LP and natural regulator is the "spring." Sometimes this is in a separate little assembly, and sometimes you can pull the plug out (the part you turn) and pop a different spring in there.


!!! DOH !!! here it is here:

http://tweetys.com/230-single-stage-regulator.aspx


That's not much of a regulator. While it's rated for 140,000 BTU, it's a cheap, portable device designed for stuff like BBQ's. Frankly, i'd be lookin for something better. YOUR LIFE depends on this

 

[4spdragtop]

Hey dart, I called Marshall Brass Co, thats who makes the reg. I told them what I was doing and he said it would work. it has 1/4" inlet and 3/8 outlet. He never mentioned flow, just the btu's. My furnace is 45k and the regulator is good for 140k so all should be good!!! I HOPE!!! Now I gotta go buy another hose, me being a dumbass forgot the one that goes from the pigtail to the reg!! Maybe I should do some Christmas shopping while I am out LOL