Pipe Size for Mr. Heater Propane Heater

[8Ball]

I just picked up a propane fueled 75K BTU Mr. Heater unit for my garage. I would like to run black pipe to a 100lb tank behind my garage. Would anyone have any suggestions on pipe size? What does the hookup generally look like on the outside by the tank? I already talked to a local propane dealer but I forgot to ask these few questions. I figured I'd also ask the folks here what your experience or advice would be with similar setups.

Thanks

 

[Junkman]

I piped mine from the tank with 3/4" soft copper to a 1/2" black iron pipe in the garage. Mine is hard piped right to the heater, and I have a drip leg just before it enters the heater. The length of the run will determine the size of the piping that you use. I used the 3/4" soft copper on the outside, since I know that when it gets cold, that the pressure will drop as a result. Once it is inside the garage, it is protected from the cold, so there is less pressure drop. In my case, the propane company made the suggestions and I did the work. It works fine and I am very pleased with my Mr Heater.

 

[mulepackin]

My installation material that came with my HD 75 NG had a specification table for gas pipe sizing, taking into account the distance run, etc. If you don't have it or can't find it, I would be glad to try to look it up for you.

 

[beetroot72]

When connecting gas supply, the length of the run from the meter
must be considered in determining the pipe size to avoid excessive
pressure drop. A line pressure of 7" w.c. (178mm w.c.) for natural
gas should be maintained when sizing piping. A line pressure of 13"
w.c. (330mm w.c.) should be maintained for liquefied petroleum
(LP) gas. For correct sizing of piping, refer to the (American)
National Fuel Gas Code ANSI Z223.1 or (Canada) CSA B149.1,
Natural Gas and Propane Installation Code or consult the utility
having jurisdiction.
A drip leg should be installed in the vertical pipe run to the unit. In
some localities, codes may require that a manual main shutoff
valve and union (furnished by installer) be installed external to the
unit. Union must be of the ground joint type. A drip leg should be
readily accessible to permit cleaning and emptying. See figure 8 .
NOTE If a switch box is mounted over electrical knockouts on back
of unit, leave a minimum of 4" (102mm) clearance between switch
box and drip leg.
A 1/8" NPT plugged tap shall be installed immediately upstream of
the gas supply connection to the heater.
NOTE Compounds used on threaded joints of gas piping must be
resistant to the actions of liquefied petroleum gases.

 

[8Ball]

Great info! Thanks!