Propane- How much is enough/ Instant on water heater

Kwajdiver · November 27, 2006, 01:27:51 PM

How much propane is enough. My MCI-9 has a 90 gallon tank. It's huge.... My frig, oven/stove, are the only thing that runs on propane. I plan to install a furnace in the very near future. Does anyone use a instant-on water heater in a coach? Any reason why not to install one??

Keep in mind, My company could send me anywhere in the USA for 3-5 months at any time. They are not concern about the weather, but I am......

Bill Williamson
MCI-9
Auto

Eagle · November 27, 2006, 01:43:41 PM

A 90 gallon tank will be very efficient for anything that you will need. Each gallon of propane has ABOUT 103000 BTU in it so you can calculate how many hours the propane will last by calculating the total number of BTU's that you will be burning per hour. With a 90 gallon tank you will have about 72 gallons of propane as it will only be filled to 80% of capacity.

gumpy · November 27, 2006, 02:25:58 PM

While I'm not a proponent of fixed LP tanks, I also believe in the mantra of, "if it ain't broke, you're not trying hard enough" or something to that effect.

If the tank is installed and working, I see no reason to remove it or add to it. If you're concerned it might be too small, then install a quick connect fitting and get a portable tank to carry along (20#, 30#, or 40#) in case you run out at the most inopertune time.

On our coach, we only have the stove/oven on propane, but we also use it go cook outside on the big camp grill. I carry two 40# tanks, and in 3 years, a trip to AK and multiple trips to WY and CO, I have not yet filled one of the tanks. I've used off both as we often remove one tank for the camp grill and still cook stuff inside off the other.

On the flip side, my father-in-law traveled with us to AK, and has two 30# tanks on his trailer with propane water heater, heater, and cooktop, and he had to fill his tanks about 3 times. There was a leak or two that we had to work on, but I don't think that was a major cause of loss.

The appliances can add up.

jaybe_2 · November 27, 2006, 03:36:42 PM

A 90 gallon tank is big! I have a propane filling station and most big stick and staple rigs have less than 30 gallon tanks and most of them have two furnaces.

msheldon · November 27, 2006, 03:39:51 PM

The biggest consumer of LP is the furnace. They work fine, but they're not terribly efficient.

Because I rarely need heat, my two 30# tanks last me all year (or more) running my water heater, fridge and stove. Granted, I only turn the water heater on when I need it, but I run the fridge on it 24/7 when I'm out, because we never have electrical hookups.

My only arguments against a single tank that size is:
#1 You have no spare if you run it dry.
#2 You're going to have to drive to the supplier to fill it. Unhooking it and throwing it in your car really isn't an option.

TomC · November 27, 2006, 04:09:37 PM

I have a 100# frame mounted tank (20gal). I only have the stove/oven and 35,000btu furnace. On average, I refill once a year. 90 gal is alot, but unless you really need the space, leave well enough alone. Good Luck, TomC

TomCat · November 27, 2006, 04:34:05 PM

I have a frame mounted 86 gallon Manchester LP tank installed on my bus. A 5.5kw Onan, 2 burner cooktop, and RV500 demand water heater are my only draws on the LP supply. I don't use the cooktop all that often, and when plugged into the power pole, don't run the genny more than an hour per month (exercise), which leaves the RV500 as my main LP user. The RV500 claims to make 940 gallons of hot water on a single 20# bottle. If that is accurate, I should be able to make around 13,000 gallons of hot water with the LP I can carry on board. I also built an Extend A Stay tee into my LP system, so in the rare case I do run out of LP, I can connect a 20# or larger bottle and get by for a bit longer.

Jay
87 SaftLiner

skihor · November 27, 2006, 04:40:23 PM

my tank is 40 gallon. It heats water and furnace. My bus has single pane windows and stock insulation in the walls. No floor insulation either. Anyway in the dead of winter here in Denver that 40 gal. will last 3 weeks. We live in it so we keep it heated 24/7.

Don & Sheila

Ross · November 27, 2006, 05:53:22 PM

I'm slowly doing away with the propane burning appliances. I have an RV500 that is now disconnected since the Proheat domestic water loop is up and running. The RV500 will be on the flea market table at Arcadia.

Ross

Kwajdiver · November 27, 2006, 06:06:39 PM

Thanks for all the input. My huge tank is starting to look really bad. It is going to need be removed, and sandblasted and painted or replaced. It also needs to be relocated to a different bay. NOT really happy with it being in the battery (house) and gen bay. So,,,, while I have it removed, I'm thinking of putting a smaller tank in the front bay.

Oophs, just looked up the spec on the tank, I believe it is only 70 gallons. It is still huge, if I don't need that much..... sorry, still learning....

Thanks,

Bill

Dale MC8 · November 28, 2006, 09:49:46 AM

Yeah Bill, it should be moved away from your battery bank/generator compartment for safety reasons. Any spark producing equipment is not allowed in a LP compartment according to the codes/regulations/whatever-they-are-called for RV construction.

You might think about shielding your generator from your batteries also. A spark from it could ignite the hydrogen gas escaping from the batteries and the other gases from the batteries could cause generator corrosion.

My $0.02 worth.

Dale