Outer Limits 4x4 Board

Just throwing this out there.
Is it possible to convert a cars AC system to a heat pump? I know it's not difficult with commercial sized AC systems, but on a car is the TX valve located in a place that'll make this difficult?

Modern cars have it already, but my diesel work car is just a bit too old (2000).

BTW I don't mean permanent conversion, I mean switchable, even if it requires manual valving.

cold permanent or hot permanent i can see just a matter of swapping hoses from heat sink to cold plate


but i may be possible to do what you want to do

Would a TX valve work acceptably in reverse or would it be necessary to bypass it and install another one near the front radiator?

Why would you want to do this when you have a heat sorce already, it could
be done and yes you would need a non return valve around both tx valves.
And a reversing valve.

HIGH ROLLER wrote:Why would you want to do this when you have a heat sorce already, it could
be done and yes you would need a non return valve around both tx valves.
And a reversing valve.

Because when it's -10 outside modern diesels don't produce enough waste heat for comfort. Especially in slow driving.
I'm thinking a reversing valve and non-return valves could be replaced with two manual diverter valves. I need to draw the layout to check.

Closer inspection looks like it would be quite tricky.
Hose sizes are working against me and the TX valve appears to be on the passenger side of the firewall where room to work is non existant.

I'd like to find a new car with both a reverse cycle air con and an engine bay uncluttered enough that I can see it.
Sounds like mission impossible.

what would running a hotter thermostat do for you ? Or would it mess with other sensors to much (I am guessing it would)

love_mud wrote:what would running a hotter thermostat do for you ? Or would it mess with other sensors to much (I am guessing it would)

The main problem is getting to running temp. Once it's at full temp it's okay but this can take 10-15 minutes of open road driving in the very cold to get the interior to a comfortable climate. In slower driving it can take a long time to warm up and running the heater inside (for the small amount of heat you get) means it takes even longer.

Maybe I should just earn more money and shoot it for a skoda. Heated seats, heated mirrors, made for the cold. I don't know exactly what system they use but tdi audi's have hot air within seconds of startup.

Put another jumper on, ya sook!

12volt electric heater would be easy wouldn't it? Never used one but it could be an option.

rowenb wrote:12volt electric heater would be easy wouldn't it? Never used one but it could be an option.

You can only pull around 10 amps from the cigarette lighter, 120watts isn't much. Maybe half a kw with a dedicated heater and wiring.
I've heard some Isuzu's in Europe had an electric ceramic heater in them. Might be worth checking the wreckers then.

Why not just move to Australia.

Cris

KiwiBacon wrote:Because when it's -10 outside modern diesels don't produce enough waste heat for comfort. Especially in slow driving.

Huh? You're saying that a modern diesel doesn't reach a "normal operating temperature" during slow driving? Are you sure your thermostat is operating properly?

Have you considered trying to capture exhaust heat somehow? Wrap copper pipe around your exhaust (do you have a catalytic converter?), and connect that into a closed loop heating system using your existing heater core?

-Scott- wrote:Huh? You're saying that a modern diesel doesn't reach a "normal operating temperature" during slow driving? Are you sure your thermostat is operating properly?

Have you considered trying to capture exhaust heat somehow? Wrap copper pipe around your exhaust (do you have a catalytic converter?), and connect that into a closed loop heating system using your existing heater core?

Yes. Modern di diesels don't warm up at idle, they need load.
In slow driving in cold conditions you can strip heat out of the cabin faster than the engine can put it back in. Thermostat works fine. I don't have an EGT gauge on this engine but at low loads exhaust heat isn't much.

Yes thats absolutely true - one of the advantages of fitting a water cooled alternator is that the heat generated by the alternator significantly decreases the warm up time of the engine.

That's the "problem" with modern efficient engines !

I recall seeing adverts in a Land Rover mag from the UK years ago about a petrol heater that could be fitted to the defenders/110's/90's etc that would help heat the cab separately from the engines heating/cooling system. I tried a quick google and found that they seem to be referred to as supplementary heaters. Some links:

http://www.eberspacher.com/products/air-heating/" onclick="window.open(this.href);return false;
http://www.eberspacher.com/products/water-heating/" onclick="window.open(this.href);return false;
http://www.webasto.com.au/am/en/am_rv_heaters.html" onclick="window.open(this.href);return false;

Possibly worth looking at??

stuee wrote:I recall seeing adverts in a Land Rover mag from the UK years ago about a petrol heater that could be fitted to the defenders/110's/90's etc that would help heat the cab separately from the engines heating/cooling system. I tried a quick google and found that they seem to be referred to as supplementary heaters. Some links:

http://www.eberspacher.com/products/air-heating/" onclick="window.open(this.href);return false;
http://www.eberspacher.com/products/water-heating/" onclick="window.open(this.href);return false;
http://www.webasto.com.au/am/en/am_rv_heaters.html" onclick="window.open(this.href);return false;

Possibly worth looking at??

Apparently some new audis have webasto heaters fitted stock. Complete with a remote that can switch them on from hundreds of metres away.
Heating the engine coolant but making the heater work as soon as you're in.

But probably overkill for my needs.

KiwiBacon wrote:

stuee wrote:I recall seeing adverts in a Land Rover mag from the UK years ago about a petrol heater that could be fitted to the defenders/110's/90's etc that would help heat the cab separately from the engines heating/cooling system. I tried a quick google and found that they seem to be referred to as supplementary heaters. Some links:

http://www.eberspacher.com/products/air-heating/" onclick="window.open(this.href);return false;
http://www.eberspacher.com/products/water-heating/" onclick="window.open(this.href);return false;
http://www.webasto.com.au/am/en/am_rv_heaters.html" onclick="window.open(this.href);return false;

Possibly worth looking at??

Apparently some new audis have webasto heaters fitted stock. Complete with a remote that can switch them on from hundreds of metres away.
Heating the engine coolant but making the heater work as soon as you're in.

But probably overkill for my needs.

I believe its an option on the diesel Range Rover Vogues too (only found that after googling). Automatically activates at -5 but also able to be remotely switched or turned on from in the cab. Be nice to have the $$$ to afford either

has anybody thought about fitting a glow plug in the input line of the heater?
it works for preheating oils when run as fuel!

hillbilliywheelchair wrote:has anybody thought about fitting a glow plug in the input line of the heater?
it works for preheating oils when run as fuel!

How many amps does a glow plug draw?

KiwiBacon wrote:

hillbilliywheelchair wrote:has anybody thought about fitting a glow plug in the input line of the heater?
it works for preheating oils when run as fuel!

How many amps does a glow plug draw?

Most glow plug fuses are around the 50 amp mark from memory .. so somewhere just under that I would think.

KiwiBacon wrote:

-Scott- wrote:Huh? You're saying that a modern diesel doesn't reach a "normal operating temperature" during slow driving? Are you sure your thermostat is operating properly?

Have you considered trying to capture exhaust heat somehow? Wrap copper pipe around your exhaust (do you have a catalytic converter?), and connect that into a closed loop heating system using your existing heater core?

Yes. Modern di diesels don't warm up at idle, they need load.
In slow driving in cold conditions you can strip heat out of the cabin faster than the engine can put it back in. Thermostat works fine. I don't have an EGT gauge on this engine but at low loads exhaust heat isn't much.

look at it from a different angle??

how about you put a blind over 1/2 to 2/3 of the radiator (experiment with how much to cover) so you have less cold air passing through the core. A mate of mine had a road bike he used in the aussie alps in winter, it wouldnt run without the radiator completely covered as it never reached operating temp.
would cost next to nothing, just remember to take it out when the weather warms up again

or put an extra jumper on and have a nice warm cup of HTFU

80's_delirious wrote:look at it from a different angle??

how about you put a blind over 1/2 to 2/3 of the radiator (experiment with how much to cover) so you have less cold air passing through the core. A mate of mine had a road bike he used in the aussie alps in winter, it wouldnt run without the radiator completely covered as it never reached operating temp.
would cost next to nothing, just remember to take it out when the weather warms up again

A radiator blind won't help as heat leaving the system isn't the problem, it's getting the heat to start with.

80's_delirious wrote: or put an extra jumper on and have a nice warm cup of HTFU

A nice warm cup of anything sounds good when it's -6 inside the car.

I like the glowplug idea, might have to investigate it further becuase I have some spares.

Spin the compressor around so that it runs backwards.

-Scott- wrote:Spin the compressor around so that it runs backwards.

Swapping the lines over would work better.
But the TX valve location and pipe sizes means it's not going to be easy to do that way. If I can get 500w (40amps, 12v) from a glowplug in the heater line then that's great. It'll also be ~1kw more load on the engine which will help idle warmup too.

KiwiBacon wrote:
A radiator blind won't help as heat leaving the system isn't the problem, it's getting the heat to start with.

?? this confuses me (easy to do lol )

I would think it is fair to say that the same engine in the same truck making the same trip in either summer or winter is going to use approximately the same amount of fuel, and will produce the same amount of heat in burning the fuel. The heat is generated and contained within the same engine, vehicle etc, the same volume of coolant, the same cooling system, radiator surface area etc

The difference is ambient air temps and therefore the amount of heat lost from the system is going to change relative to the ambient air temp (more or less), the amount of heat generated is NOT going to change a lot. No?
Reduce the exposure of the radiator and engine bay to the cold air flowing through it and you will retain the heat that is put into the system for longer. Even at low speed, low load running, a diesel is going to produce EGTs of what? 100-C - 200-C minimum? At that level, surely the engine will reach operating temp at some point if you can limit the amount of heat lost from the system?

10minutes with a peice of cardboard and some duct tape, and you could easily test the idea

My imported JDM 80 series had insulated plastic splash guards under the front bar and engine and gearbox and around the back of the headlights and battery trays which all reduced the airflow throught the engine bay. Along with 24volt starter, glow plugs and fuel pre-heat, I assumed they were to help it in cold climate running conditions.
Similar guards could help you?

80's_delirious wrote: ?? this confuses me (easy to do lol )

I would think it is fair to say that the same engine in the same truck making the same trip in either summer or winter is going to use approximately the same amount of fuel, and will produce the same amount of heat in burning the fuel. The heat is generated and contained within the same engine, vehicle etc, the same volume of coolant, the same cooling system, radiator surface area etc

The difference is ambient air temps and therefore the amount of heat lost from the system is going to change relative to the ambient air temp (more or less), the amount of heat generated is NOT going to change a lot. No?
Reduce the exposure of the radiator and engine bay to the cold air flowing through it and you will retain the heat that is put into the system for longer. Even at low speed, low load running, a diesel is going to produce EGTs of what? 100-C - 200-C minimum? At that level, surely the engine will reach operating temp at some point if you can limit the amount of heat lost from the system?

I don't beleive enough heat is lost through the radiator before the engine is warm to make any difference. Well it shouldn't be if the thermostat is doing it's job properly. I should poke around with a thermometer on radiator hoses when it's warming up to check this.
The other problem is the wide swing in ambient temperatures. The same week here (the week before last) produces temperatures from -10C to +15C. A radiator blind could cause other problems when it's 15 degrees.

80's_delirious wrote:
My imported JDM 80 series had insulated plastic splash guards under the front bar and engine and gearbox and around the back of the headlights and battery trays which all reduced the airflow throught the engine bay. Along with 24volt starter, glow plugs and fuel pre-heat, I assumed they were to help it in cold climate running conditions.
Similar guards could help you?

Did you get a snow sticker somewhere under the bonnet to go with that? I've heard of a cold weather pack but people unsure of what was in it.
I need to make up a sump guard for this car which will serve some of that function. Based the sump out late last year.

KiwiBacon wrote: Did you get a snow sticker somewhere under the bonnet to go with that?

How do you spell snow in Japanese??

lots of the engine bay stickers are Japanese characters only. I have heard of the snow pack, but not really sure what was in it. No sticker that I am aware of.

The other reason I'm not headed towards the radiator blind is the time.
I'm looking for ways to get heat within a minute or two, the electric heaters or reverse aircon seem to be the only reliable ways to do that. A radiator blind might hasten the time to fully warm, but it's not going to defrost the car before I drive off.

[quote


Maybe I should just earn more money and shoot it for a skoda. Heated seats, heated mirrors, made for the cold. I don't know exactly what system they use but tdi audi's have hot air within seconds of startup.[/quote]

They have an variable 1000w heater panel in duct next to heater core.

Bazzle