Ducting 3

Le Tonkinois Varnish

B & D Murkin

UK main importers for

Le Tonkinois varnish

Flexidisc sander

Ducting Ratings - Airtronic D2 D4 D4 PLUS

Read pages 1 and 2 before proceeding, they contain explanations

The following pages have more models and calculation examples

Airtronic D2 ducting ratings

Part	description		additional notes	Single duct rating
1	Grille (Inlet & Outlet)	60 mm		0.4 or 0
2	Ducting flange connecting socket	60 mm		0 or 1.7
3	Flexible pipe	60 mm	Per metre	1
**	Flexible pipe larger size	75 mm	Per metre	[ 0.4 ]
**	Flexible pipe larger size	90 mm	Per metre	[ 0.2 ]
**	Flexible pipe larger size	100 mm	Per metre	[ 0.1 ]
3a	Flexible pipe 90 degree bend	60 mm	Additional to length rating	0.2 or 1.2
4	Protective grille	60 mm	Heater inlet - twist on	0
5	Heater outlet hood straight	60 mm		0
6	Heater outlet hood 90 degree	60 mm		4.8
7	90 degree bend, plastic elbow	60 mm	Fitting into hood only	4
8	T - piece offset 90 degree	60 60 60	Straight through path 90 degree path	0.25 1.4 or 0.6?
9	Y - piece offset 45 degree	60 60 60	Straight through path 45 degree path	0.25? 1 or 0.3?
10	Butterfly valve with regulating flap Position middle Position right / left	60 60 60	Equal split All to one outlet	1.2? 0.6
11	Outlet grille with connector	60 mm	Rotatable	3.2 or 1.4
12	Ducting flange connecting piece	60 mm		0
13	90 degree upright vent	60 mm	Rotatable	0.8
14	30 degree outlet screen flat	60 mm	Rotatable	0.5
15	Outlet screen closeable	60 mm	Rotatable	Not applicable


**	Larger ducting ratings change	60 to 75	[ 60 mm rating x 0.41 ]
**	Larger ducting ratings change	60 to 90	[ 60 mm rating x 0.20 ]
**	Larger ducting ratings change	60 to 100	[ 60 mm rating x 0.13 ]

The duct parts drawings show several typical ducting combinations.

Use them to identify the individual component and then look up its rating in the tables below.

Ratings are for single path ducting, refer to page 1 for dual duct installations.

Refer to notes bottom of page for blue and ‘?’ Entries.

Part	description		additional notes	Single duct rating
16	Grille (Inlet & Outlet)	75 mm		0.5
17	Ducting flange connecting socket	75 mm		0
18	Flexible pipe	75 mm	Per metre	1
**	Flexible pipe smaller size	60 mm	Per metre	[ 2 ]
**	Flexible pipe larger size	90 mm	Per metre	[ 0.5 ]
**	Flexible pipe larger size	100 mm	Per metre	[ 0.3 ]
18a	Flexible pipe 90 deg bend	75 mm	Additional to length rating	0.2 or 1.2
19	Heater outlet hood straight	75 mm		0
20	Heater outlet hood 90 degree	75 mm		6
21	90 degree bend, plastic elbow	75 mm	Fitting into hood only	4.5 or 3
22	T - piece offset 90 degree	75 75 75	Straight through path 90 degree path	0.25? 0.8
23	Y - piece offset 45 degree	75 75 75	Straight through path 45 degree path	0.25? 0.5
24	Y - piece symmetrical	75 60 60	75 to 60 mm reduction	0.8 0.8
25	Ducting flange connecting piece	75 mm		0
26	90 degree upright vent	75 mm	Rotatable	0.8
27	30 degree outlet screen flat	75 mm	Rotatable	0.5
28	0 degree outlet screen flat	75 mm	Rotatable	0.5
29	Outlet screen closeable	75 mm	Rotatable	Not applicable
30	Outlet vent with flange	75 mm	Rotatable	0.5
31	French vent with flange	75 mm	Closeable	Not applicable
32	Adaptor ring	60 to 75	60 to 75 mm	0?
33	Ducting union straight	75 mm		0.5 or 0.1
34	Air silencer (Inlet & Outlet)	75 mm		0.7 or 1
35	Butterfly valve with regulating flap Position middle Position right / left	75 75 75	Equal split All to one outlet	1.2 or 1.5 0.5


**	Smaller ducting ratings change	75 to 60	[ 75 mm rating x 2.44 ]
**	Larger ducting ratings change	75 to 90	[ 75 mm rating x 0.48 ]
**	Larger ducting ratings change	75 to 100	[ 75 mm rating x 0.32 ]

Airtronic D4 / D4 Plus Ducting Ratings

Airtronic D2 with 60mm diameter outlet hood (Heater rating 6)

Airtronic D2 with 75mm diameter outlet hood (Heater rating 12)

Part	description		additional notes	Single duct rating
1	Grille (Inlet & Outlet)	75 mm		0.4 or 1.4
2	Ducting flange connecting socket	75 mm		0
3	Flexible pipe	75 mm	Per metre	1
**	Flexible pipe smaller size	60 mm	Per metre	[ 2 ]
**	Flexible pipe larger size	90 mm	Per metre	[ 0.5 ]
**	Flexible pipe larger size	100 mm	Per metre	[ 0.3 ]
3a	Flexible pipe 90 degree bend	75 mm	Additional to length rating	0.2 or 1
4	Protective grille	75 mm	Heater inlet - twist on	2
5	Heater outlet hood straight	75 mm		0
6	Heater outlet hood 90 degrees	75 mm	Do not use with D4 Plus	2
7	T - piece offset 90 degree	75 75 75	Straight through path 90 degree path	0.2? 0.5
8	Y - piece offset 45 degree	75 75 75	Straight through path 45 degree path	0.2? 0.6? higher than 90 degree part 7?
9	Ducting flange connecting piece	75 mm		0 or 1.4
10	90 degree upright vent	75 mm	Rotatable	1.1
11	30 degree outlet screen flat	75 mm	Rotatable	0.3
12	0 degree outlet screen flat	75 mm	Rotatable	0.3
13	Outlet screen closeable	75 mm	Rotatable	Not applicable
14	Outlet vent with flange	75 mm	Rotatable	0.7
15	French vent with flange	75 mm	Closeable	Not applicable
16	Air silencer	75 mm		1
17	Adapter ring	75/90 mm		0.5


**	Smaller ducting ratings change	75 to 60	[ 75 mm rating x 2.44 ]
**	Larger ducting ratings change	75 to 90	[ 75 mm rating x 0.48 ]
**	Larger ducting ratings change	75 to 100	[ 75 mm rating x 0.32 ]

Airtronic D4 with 75mm diameter outlet hood (Heater rating 3)

Airtronic D4 Plus with 75mm diameter outlet hood (Heater rating 10)

Part	description		additional notes	Single duct rating
18	Heater outlet hood straight	90 mm		0
19	Heater outlet hood 90 degrees	90 mm	Do not use with D4 Plus	5
20	Flexible pipe	90 mm	Per metre	1
**	Flexible pipe smaller size	60 mm	Per metre	[ 5 ]
**	Flexible pipe larger size	75 mm	Per metre	[ 2 ]
**	Flexible pipe larger size	100 mm	Per metre	[ 0.7 ]
	Flexible pipe 90 degree bend	90 mm	Additional to length rating	0.2
	T - piece offset 90 degree	90 90 90	Straight through path 90 degree path	0? ?
22	Butterfly valve with regulating flap Position middle Position right / left	90 90 90	Equal split All to one outlet	1.2 1.4 D2 part 35 has equal split higher than r/l
23	Y - piece offset 45 degree	90 90 90	Straight through path 45 degree path	0 ? 0.5 ?
24	Y - piece symmetrical	90 75 75	90 to 75 mm reduction	0.9 0.9
25	Ducting flange connecting piece	90 mm		2.2 or 1? or 1.4?
26	90 degree upright vent	90 mm	Rotatable	2.4
27	30 degree outlet screen flat	90 mm	Rotatable	2 or 2.4?
28	0 degree outlet screen flat	90 mm	Rotatable	1.1
29	Outlet screen closeable	90 mm	Rotatable	Not applicable
30	Outlet vent with flange		Rotatable	2.4
	Y - piece symetrical	90 90 90		?
31	Adapter ring 90 to 100 mm	90 to 100		0
32	Flexible pipe	100 mm	Per metre	0.4 or 1
33	Air silencer	100 mm		0.5 or 1
34	Ducting union straight	100 mm		0.1
35	Y - piece offset 45 degree 100 100 100	100 mm	Straight through path 45 degree path	0 0.5
36	Reducer	100 to 75		3.2


**	Smaller ducting ratings change	90 to 60	[ 90 mm rating x 5.07 ]
**	Smaller ducting ratings change	90 to 75	[ 90 mm rating x 2.07 ]
**	Larger ducting ratings change	90 to 100	[ 90 mm rating x 0.64 ]

Airtronic D4 with 90mm diameter outlet hood (Heater rating 10)

Airtronic D4 Plus with 90mm diameter outlet hood (Heater rating 15)

Figures in blue show different ratings from older manuals, also any ratings that look suspect.

At this time I have no idea which of these are correct, hopefully they will be sorted out later.

Where the difference is small I have chosen a single value shown in blue.

? Best guess or rating figure not known, treat as very tentative.

**Eberspacher heater duct rating is for ducting the same diameter as the heater outlet hood.

In practical installations the duct size may be changed anywhere along its length.

The table lists the equivalent ratings just for the different sized pipe.

The value for other items can be calculated by multiplying by the figures at the bottom of the table.

[ ] Figures within square brackets are from my own calculations, not from Eberspachers manuals.

When a right angled hood is fitted to a D4 Plus it creates turbulence that can damage the heat exchanger.

D4 or D4 Plus case damaged by overheating.

This is probably the result of the D4 Plus turbulence.

Home Eberspacher Duct 1 Duct 2 Duct 3 Duct 4 Duct 5 Site guide

Why a right angled hood is not permitted with a D4 Plus

Eberspacher Top^< Previous Next >

Ducting Ratings - Airtronic D2 D4 D4 PLUS

Airtronic D2 ducting ratings

Airtronic D4 / D4 Plus Ducting Ratings

Why a right angled hood is not permitted with a D4 Plus

Continues on next page