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Questions on heater / demister.
Rosco - 7/11/10 at 02:19 PM

I'm looking at options for cabin heater and demister installation on my Fury and struggling to get my head around it. Apprecaite any comments on the best way forward and/or my questions below.

1. What's best for the air intake; the engine bay, cabin or external via ducting? Looking at available heaters most appear to be bulkhead mounted taking air from either the engine bay or recyling air from the cabin.

2. How do you control the temperature? Speed control appears limited for most available fans. I see adverts for control valves for the water circuit, but am concerned this will disrupt the cooling circuit for the engine - Note I'm running a Toyota 4AGE.

3. Has anyone considered ducting exhaust heat as an alternative to a water matrix? This would be really easy on a Fury since the exhaust is enclosed in the sill and could easily be ducted into the cabin with aid of a small fan. Alternatively you could duct it from the exhaust manifold, which I assume is how old air-cooled cars worked - Beetles, 2VC, 911.. so why not a kit car, it would save a little weight and cost?

4. What sort of KW output do I need to heat the cabin and demist - most look to be 2KW to 3KW?

5. Any recommendations on heaters, something light, cheep, small, easy to install?


Many thanks


BenTyreman - 7/11/10 at 02:45 PM

If you haven't IVA tested yet, then the air intake must not be taken from near the vehicles exhaust outlet or draw air from within an engine compartment. If you draw air from within the cabin then it should be able to generate a hotter cabin.

You can get a bypass valve rather than a stop valve to control the temperature.


matt_gsxr - 7/11/10 at 02:58 PM

Ducting engine bay air may be frowned upon, but I have a couple of vents in my tunnel that are quite good for getting heat in to the footwells. No fan is needed owing to engine bay being slightly pressurized. Interestingly it wouldn't work if the underside of the engine bay and tunnel weren't panelled.

I would worry about ducting air from around the exhaust because of the potential for carbon monoxide inhalation.

Highly precise temperature control on an open top car is probably un-necessary (to my mind).

Matt


BenTyreman - 7/11/10 at 03:00 PM

Ducting engine bay air is not just frowned upon, it's expressly forbidden in the IVA manual.


RazMan - 7/11/10 at 03:05 PM

With any demisting application you will always benefit from taking in outside air, otherwise you are just recirculating internal (and moist) air. I wouldn't duct in from the engine bay due to the possibility of nasty fumes - I ducted mine in from under the wheelarch through a computer fan filter to stop debris entering the fan. Mine is a CBS 2kW jobbie which works fairly well.


BenB - 7/11/10 at 03:12 PM

quote:
Originally posted by BenTyreman
Ducting engine bay air is not just frowned upon, it's expressly forbidden in the IVA manual.


Which to be fair is understandable. It completely voids any fire-resistance imparted by the bulkhead. An engine bay fire with a big fan sucking engine bay air into the cockpit would probably be bad


lsdweb - 7/11/10 at 04:16 PM

You could try one of those ceramic heaters and duct the air to some vents. They're only about 200 watts max though.

Wyn


adithorp - 8/11/10 at 04:54 PM

I passed SVA with 2 smallfan heaters from a caravan shop. One mounted each side under the dash blowing onto the screen.
Otherwise a VW Polo (mk2/3 I think) heater will fit on the scuttle. Comes as a unit with heat control and fan.

I'll post pictures of my setup later and I think I've some of a polo heater.

Edit... Photos

polo heater 1

Polo Heater 2

Sorry, none of the caravan ceramic blowers I used.

[Edited on 8/11/10 by adithorp]