Webasto Heater Installation

[Mark Laurnen]

Happy New Year to all! I’m looking for advice pertaining to diesel fuel supply to a Webasto air heater. Webasto recommends that the heater have its own fuel line independent of any other machinery. They fear any running engine or generator could rob the heater if they share a common fuel source line. My yard wants to remove the cockpit deck of my 32 TE in order to access the top of the fuel tank ... probably about $2K just for the deck r/r. Do any of you have suggestions for an alternative approach to securing a reliable fuel supply from the main tank? Thanks!

[Tree]

Why not just add a small remote tank - they hardly use any fuel so you won’t need to top it up that often.

I’m considering adding hearing to mine and that’s all I will do.

Alternatively you could add a T-piece at the racor filter which is easily accessible and run the tube back from that?

[Mark Laurnen]

Thanks for your reply. I don’t see why it wouldn’t work to t-piece (with stopcock?) off one of the main lines before the Racor. I guess at full throttle the engine could deprive the heater, but at anything less than that it seems there could be adequate flow for both. The Webasto rep did say that the heater fuel supply line is neutral pressure and could have pressure drawing against the negative line pressure generated by a running motor. I’m wondering if I can access the main tank without pulling the cockpit deck.

[Tree]

In an ideal world, coming from the tank direct is perfect but adding a T before the racor will work just fine.

My buddy is currently running his generator, HVAC and engine from the same line all from two T pieces.

With regards to the engine starving the line, he has a Volvo D6 310, a 3kw generator and the heating side of the HVAC is an eberspacer and the fuel tanks are actually below the lift pump on the engine and dosing pumps for generator and heating. Priming them is a PITA but otherwise no issue.

[dkirsop]

Any chance you could install a deck plate to access the tank from above to install a separate pickup and fuel shutoff cock?

[Pitou]

I can understand why you don't want to incur the expense of doing R&R on the deck and installing another pickup tube, but it is the right way to do the job. As you seem to be inclined and with the Webasto Air Heaters burning only 6 1/2 to 23 ounces of fuel per hour, I'd first "T" into the current fuel line and give it a shot. I'm not usually one who takes a short cut, but in this instance I think that installing a "T" is viable.

If you do decide to "T" into an existing line, be sure to set things up with fuel filters etc. so that if you do end up needing to go back to R&R the deck to add the heater's own pickup tube only a minimal amount of the already done work needs to be redone (from the fuel filter back).

[Pitou]

I can understand why you don't want to incur the expense of doing R&R on the deck and installing another pickup tube, but it is the right way to do the job. As you seem to be inclined and with the Webasto Air Heaters burning only 6 1/2 to 23 ounces of fuel per hour, I'd first "T" into the current fuel line and give it a shot. I'm not usually one who takes a short cut, but in this instance I think that installing a "T" is viable and from Tree's description and friend's experience, this should work.

If you do decide to "T" into an existing line, be sure to set things up with fuel filters etc. so that if you do end up needing to go back to R&R the deck to add the heater's own pickup tube only a minimal amount of the already done work needs to be redone (from the fuel filter back).

[Mark Laurnen]

Thank you to all of you. I really appreciate the support and advice. I think I will plan to proceed with tapping into an existing line first and, as Kevin suggested, be prepared to bring a dedicated line to that point if necessary. Maybe the fuel line to the generator would make most sense as it’s fuel draw is less than that of either motor. Also, the main point of adding the Webasto is to have heat without running the generator so in all likelihood they would not frequently be running simultaneously.

[Pitou]

If you utililize the generator fuel line, consider tying in at the fuel filter head which is most likely the Racor 120A. It has 4 fuel line ports (2 unused if setup like my factory Northern Lights 6kW Albin install).

The 120A is rated at 15 gph and the Northern Lights burns .59 gph at full load. Your combined fuel burns are well within the limits of the filter. The only number that I don't have is how much total fuel is drawn to the generator per hour and sent back to the tank via the fuel return line, but I still think that you will be within the limits of the Racor.

Please let us know how you make out.

[Mark Laurnen]

Thanks Kevin, I like those numbers! My NL is rated at 5 kw so potentially even less burn. I wondered if the Racor might have more than one outlet, would save the hassel of yet another filter set up. The reason I’m hesitant to go the cockpit dec r/r flute is that they just did that a year ago ($2k) to prevent rainwater collection in the bilge. I think they jumped to conclusions because the rainwater still leaks somewhere and collects,. I think the leak could be at the cockpit deck hatch scuppers and the deck seam may have been fine all along. I recently brought this up and now they are blaming the rod storage lockers beneath the side decks ... I don’t buy that. Anyway, $2 k to r/r the cockpit sole seems like highway robbery to me. I think I’ll tap off the generator racor downstream from the element. Thanks!