Van interior warm up.

[A.D.]

Hi, thanks in anticipation of advice, I considered getting a car heater for warming the first few miles of winter journeys, I can easily spot those for sale claiming 1500w running of a cigarette lighter socket are a scam, probably only 150w.
So my plan is: 9 guage cable with a 50Amp breaker and 100Amp relay, wired to the 12v van battery, the heater would contain 8x50w halogen bulbs giving nearly 400w, the relay would be switched via a live feed, only live whilst the engine is running.

Alternatively I could use nichrome wire coiled around something suitable, but I have failed getting the right spec/details online regarding guage and length of wire to produce 400w at 12v. (The alternator is giving me about 13.7v).

Yes, probably sounds ridiculous, but that's the way I am.

Ps, the heater will be safe, safety first.

Thanks, any comments/advice would be greatly appreciated.
A.D. (Adrian)

 

[camerart]

Hi A,
How big your van is, and is there a cab, that separates the cab from the van body?
If it's all one, then hang a curtain up till the cab gets warm.

It will need quite a bit of power to heat the cab, in mid winter, you may want to experiment with an extension lead and a house heater.

I converted a van to a motorhome, and fitted a Webasto heater, cosy :0

C.

 

[Diver300]

I guess you mean a 50 A breaker and a 100 A relay.

Some cars already have electric heaters in the air ducts. I would try to find one of those. Failing that, get a bunch or resistors.

If you are using resistors, run them at around half their maximum power or less. At maximum power a lot of resistors have very high surface temperatures which can damage things around them.

If you fit a heater in the air duct, make sure that it can't be on unless their is air moving in the duct.

You can get about 15% more power by running the heaters directly from the AC (alternating current) coils of the alternator. There are three AC connections in nearly all car alternators, and the peak voltage is 15 - 16 V. You should connect between those AC connections and have no connection to ground, and the loads should be balanced in a star or delta arrangement. You would need three relays or a 3 pole contactor to turn the heaters on and off.

 

[Diver300]

Here is a heater from a VAG car. https://www.ebay.co.uk/itm/175275576406
If that link doesn't work, just search for:-

5Q0963235D

 

[A.D.]

Thanks Driver 300
Indeed, amps I meant, it's only a citroen berlingo, the heater will only be used for the first 3 or 4 miles until the engine heats up, it will be just convection unless I put a fan in it. Freestanding/fixed, it will probably resemble a 5 litre paint can. I'll read up on the resistor idea and consider the ac idea as well.