Feed tank for diesel heater.

Leighb

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I have a diesel heater (Ardic) it is currently fed from a tatty looking steel outboard tank.
This is fitted in the cockpit locker adjacent to the heater. It effectively occupies a great deal of the locker, as it is mounted on a base board that blocks off the bottom of the locker, and incidentally access to the cockpit drain seacock.

It cannot be lifted out of the locker to fill up without disconnecting the fuel feed pipe, and trying to do it in situ has the potential for messy diesel spills.
It would appear that it was originally intended to be fed direct from the main tank, as there is an extra fuel feed pipe fitted, which has been blanked off.
From reading the Ardic manual they did not check the specifications as they would have discovered that the main tank is too far below the heater for the Ardic pump to lift.

My idea is to have a small "day tank" alongside the heater, fitted to the bulkhead. This would be fed from the main tank by an electric pump, which would maintain a regular supply to the heater without the need to refill it.
Clearly there would be a need to have a float switch, or some such, in the day tank to shut off the electric pump when the tank was full.

Does any one have any experience of such a system?
What should the tank be made of, plastic or stainless?
Any suggestions for who would be good to fabricate. Tek-Tanks are one possibility, any others?
Are such switches available, I have tried googling but with no result?
The pumps are definitely available and capable of easily lifting the necessary height.
Any obvious snags that I have not foreseen?

Is there a far simpler system that I have not considered?
 
I'm not sure why you would need a separate tank for the heater supply. I'm fitting an eberspacher water heater and am taking a feed direct from main tank (via a standpipe) through the pump and on to the burner. Have you a very significant head from tank to burner which is too great for the pump to achieve?
 
Why not have a manual switch, then you can top up as necessary and keep a check on the level of the main tank.
My Mikuni runs perfectly from the main tank which is in the bilge.
 
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I'm not sure why you would need a separate tank for the heater supply. Have you a very significant head from tank to burner which is too great for the pump to achieve?

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Yes, the manual shows that the max height between the bottom of the suction pipe and the Ardic unit is 1000mm.

My main tank is under the cabin sole, and the heater is mounted quite high in the port cockpit locker. The height to the TOP of the main tank is more than that, and obviously the bottom of the feed pipe is another 350mm or so deeper.

I think the original fitter made a mistake. Reading through the installation manual it is not absolutely clear. In the text the only apparent limitation is a maximum fuel pipe length of 4.0m, it is only if you find a small diagram at the back of the manual that the max height is shown.
 
[ QUOTE ]
Why not have a manual switch, then you can top up as necessary and keep a check on the level of the main tank.
My Mikuni runs perfectly from the main tank which is in the bilge.

[/ QUOTE ]

That is a simpler solution, I guess I could just check the level before starting the heater, top up if needed and then start up.

Definitely fits the KISS requirement /forums/images/graemlins/grin.gif
 
A point you may have already considered, the importance of which will depend on how much heating oil you use:
red diesel will soon becomes illegal for your engine, but will be OK for heating use, in which case you might prefer two quite seperate fuel systems.
 
quote: red diesel will soon becomes illegal for your engine, but will be OK for heating use, in which case you might prefer two quite seperate fuel systems.

You might eventually be proven right, but that decision has not yet been finalised.

PWG
 
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