Eberspacher D2 and D4 differences

[stefan_r]

Hi, I have a D2 fitted but am thinking of upgrading to a D4.

Apart from duct size how much of a straight swap would it be?

Fuel pump, power, remote exhaust etc?

I quite want to keep the D2 as a reserve....which only makes sense if they're a reasonable straight swap...

 

[pcatterall]

The D4 is physically a little larger all round but has the same exhaust size. The duct for the d2 may be 60 or 75mm and for the d4 is 75 or 90 so you may have the correct duct allready.
The pump is the same. Both use 8.8 amps on start up so your wiring should be ok.
An easy swap I would say.

 

[Talulah]

I may be wrong bu I was under the impression that whilst the pump is the same it is calibrated differently. The metal nut (as oppossed to the brass nuts vary the calibration). If you use a pump calibrated for a bigger heater it will run lean and if you use a pump calibrated for a smaller heater it will run rich.

 

[pcatterall]

The parts list indicates the same part number for D4 and D2 I assumed that the D4 controller simply pumped at a faster rate,

 

[Talulah]

You could be right. I am just repeating what was said to me by Mr Kruger a couple of years ago. He was saying the pumps had to be matched.

 

[pcatterall]

I AM right !!! (about the part numbers at least!!) as I'm looking at the Eberspacher parts list now!! I know that there are differences with D3s for example and between the D1LC and the compact and the D2, often they will work but innefficiently, lots of smoke etc
I have not had a D4 in my workshop or tested one with the D2 pump so I have no proof that they work only what Eberspacher print!!