Alfa Romeo Forum banner

156 Auxiliary (not) heater.

7K views 27 replies 8 participants last post by  jwq 
#1 ·
So my thermostat is good (rad cold till engine hot) but my 2004 2.4 20 valve still takes an age to warm its engine and cab. Does anyone know if the auxiliary heater was specified for the British market? Mine has the 30A fuses and relays, so probably the heaters too(?), but they don't do anything (even on max de-mist setting). Can the climate control unit be re-programmed to operate the heaters? If not I might tap into the control lines and add a switch.....
PS: Do the heaters heat the air or the water?
 
#5 ·
The problem is low temperature rather than low volume of air, but I checked the filters and they're fine. The engine takes about 6miles and 15 min of slow commuting to get the coolant from 0 to 50 degrees C (after allowing for the gauge reading 5 degrees low). Is this normal with this engine?
 
#6 ·
according to elearn:

<snip>
Description
The climate control via the heater unit is insufficient when the engine is cold, especially in Diesel engines which are slow to warm up.
These engines may optionally be fitted with a supplementary heater system. This remains active from the moment when the engine is turned on until a certain temperature is reached.
The system consists of an additional heater, located in the heater unit: the device contains three resistances (PTC).
The operation of the resistances is controlled by the climate control unit which either operates only one, two or three of them, providing gradual heating, with a maximum power of 700 W following a logic which depends on:
the temperature of the engine coolant (about 60° ?);
the engine speed (which should be above 700 rpm).
the battery voltage (which should not go below 12.2 V).

The heater coil supply line is protected by a special maxifuse and two special shunt fuses located on the engine compartment partition. .
<snip>

There are 2 maxi fuses involved, one 30 amps and 1 50 amps (B38A -30 amp and B38B-50 amp ) and 2 relays, J36 & J37
 
#9 · (Edited)
only have the Dutch manual easily available, but if you look on page 171/172, you can see the relays in fig.56
http://members.chello.nl/e.beker/Handleiding%20AR%20156%20NL.pdf

fig.49 page 169 shows location of the fuses (on battery). According to the tabel on page 173, fuse 10 is the 70 amp maxifuse for heater (B99 in elearn)

B38A & B seem to be located near the heater according to elearn ?
 
#21 ·
I made an auxiliary heater,using the three glow plug 'hedgehog' type water heater from a Renault Clio 1.5 dci.
Combined with a temperature sender from a VW that turns off at around 55℃ and a relay for each plug(spare red ones from an Alfa!).
It works rather well,in as much that,with the heater control on auto,(pre interior facelift model,so no auxiliary heater of any sort),by the time the fan kicks in,the air from the heater is noticeably warm. . . . .the best bit being that I dont have to 'drive it like I stole it' when the engine is cold to avoid hypothermia!(tbh I got used to freezing,just couldn't bring myself to thrash a cold engine!)
 
#22 ·
Hello Looneymoo, thats the sort of thing I was thinking of. Did you find that the alternator coped ? I suspect that the Alfa system switches between 1, 2 or 3 heaters depending on what power is available.
A Webasto type system would be great and might be available cheaply from a scrapped Saab, but where would you put it?
 
#23 ·
Hi R.T.
the alternator so far has coped fine,the only difference I have noticed is at tickover the headlights dim a little,but as soon as the revs rise even 100rpm,normal lighting is restored.

I used the fused terminal on the bus box that the auxiliary heater uses on yours(thick white wire with a red tracer?)

I did toy with the idea of using the heater from a 320d BMW,but it needs (I think) a pwm feed from the ecu and gave up in the end and did it the easy way!I used I separate relays so I could refine the system if needed.

The webasto would be great on a cold morning but i don't know where it would fit?
 
#24 ·
....
The webasto would be great on a cold morning but i don't know where it would fit?
They usually take up releatively little space, and Webasto has dedicated step-by-step installation instructions for a large number of cars...
I've seen one or two 156's advertised with Webasto's, so it's definately possible.

Had one in the past in my Fiat barchetta, was mounted in the wheel well. Great piece of kit :)
 
#25 ·
Or maybe just a remote engine start. After all, the engine is there already, it won't add weight and little complication, it won't drain the battery, and without ram air cooling the block the engine warms up so much quicker. If combined with a "hedgehog" heater the engine would have a little load and warm faster. Much cheaper too....
 
#27 · (Edited)
Hi jwq,
I haven't seen a Webasto system in the flesh,so can't visualise where it could fit,but,there are spaces in the arches . . . might be a nice little project for next year!

With the 'hegehog' I can defrost the car by starting it and leaving it running for a few minutes,not something I make a habit of,but sometimes needs must!Before the 'hedgehog,I could leave it running for ages and the screen barely cleared!

The engine warm up is a little quicker,mainly because the heater isn't cooling the coolant before it even gets warm . . . . If I don't use the heater,warm up is quite a bit faster . . .

Hi Dave is yours the facelift interior model?my mate has one and that has a bit of extra loom to use only part of the auxiliary heater,to reduce the current used.

My thermostat is fine,runs at about 88℃,on fes.The problem is that on cold mornings,with the heater on a reasonable setting,the car(engine or heater!) doesnt warm up unless you give it some beans!
I would disconnect the 'hedgehog' if the stat goes,as it would be on for too long and give the battery and alternator a hard time
 
#28 ·
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top