Quick question -- Where to tap into tank for furnace fuel?

[Sebulba]

Hello all,

So we're going to be spending the winter in Santa Fe, NM -- not the tropics.

I have 2 Chinese diesel furnaces that I'm using - - one for front zone and one for Bed and Bath (Back) zone.  Pleased with them so far, but getting tired of filling the 10 liter tank that they came with when I have about 150 gallons of diesel just sitting there.

What suggestions do you have for tapping into the regular diesel tank? 

Add a drop pipe dedicated to the furnaces? 

Tap into an existing fuel line?

I would like to use 3/8 id fuel hose.

Thanks a million,

Seb

P.S. Progress note:  All the uppers are out and shore power is just about wired.

[Iceni John]

The heaters' supplied metering pumps will only push fuel, not pull it, and not too far.   If the bus's tank is a long way from the heaters (as my bus's is from the rear bedroom's heater), you may need to install transfer pumps to move fuel from the bus's tank to the heaters' 10-liter day tanks.   I use a pair of cheapo gear pumps that are intended for scavenging oil in dry-sump race engines, and they suck fuel from the bus's tank and move it to each day tank through 3/8" fuel hose.   Each pump can completely fill its day tank in less than a minute, and I have a momentary-on toggle switch by the day tank that actuates a relay that powers the transfer pump.   It works very well and is easy to use.   I had a spare 1/2" port in the top of the bus's tank, so I drilled out a 1/2" brass reducer bushing's thread and soldered a 3/8" stainless pickup tube into the bushing (yes, you can solder stainless!), with the bottom of the tube a few inches above the bottom of the tank.  So far, so good!

John

[buswarrior]

as noted, add a pump to fill the day tanks for the heaters.

A really slick, idiot proof solution involves the vent being a return line to the tank.

Run the pump until there's trickle, and it's full.

happy coaching!
buswarrior

[Sebulba]

The heaters' supplied metering pumps will only push fuel, not pull it, and not too far.   If the bus's tank is a long way from the heaters (as my bus's is from the rear bedroom's heater), you may need to install transfer pumps to move fuel from the bus's tank to the heaters' 10-liter day tanks.   I use a pair of cheapo gear pumps that are intended for scavenging oil in dry-sump race engines, and they suck fuel from the bus's tank and move it to each day tank through 3/8" fuel hose.   Each pump can completely fill its day tank in less than a minute, and I have a momentary-on toggle switch by the day tank that actuates a relay that powers the transfer pump.   It works very well and is easy to use.   I had a spare 1/2" port in the top of the bus's tank, so I drilled out a 1/2" brass reducer bushing's thread and soldered a 3/8" stainless pickup tube into the bushing (yes, you can solder stainless!), with the bottom of the tube a few inches above the bottom of the tank.  So far, so good!

John

That may be a good option, yes I am aware of the sucking issue.  Tha sounds bad.

I also thought of using a 15 gallon plastic tank as a day tank, as you call it, and transferring out of the big tank.  Also this way I could monitor usage.

I need to get the door open by the bus tank and see what's there.

Thanks

Seb

[Sebulba]

as noted, add a pump to fill the day tanks for the heaters.

A really slick, idiot proof solution involves the vent being a return line to the tank.

Run the pump until there's trickle, and it's full.

happy coaching!
buswarrior

Another vote for a day tank.

I have to think about what you said.  Not wrapping my mind around it yet.

Thanks

Seb

[dtcerrato]

We have two permanent diesel heaters installed on the bus now. Each has it's own 15L day(s) tank. We also have a back up electric fuel pump in the main tank to engine oem line. We use that 12V fuel pump to fill the days tanks using a flexible valved pigtail to the day tank fillers. We too want to know exact fuel being used for diesel heaters. Wished we had them 30 years ago. They save immensely on LP fuel.