Cold in the rear

[pointy]

Hi All

This is my first post, I have just bought my first coachbuilt motorhome a swift sundance 520 after having a couple of van based campers, my issue is whilst travelling there is no form of heat in the rear and as you can imagine at this time of the year it is very cold so taking my 3 year old out in it is almost out of the question unless she is going to travel with her coat and hat on lol.

 

Has anyone else had a similar issue and if so how did they get around this.

[lennyhb]

Most coachbuilts suffer with this problem, the cab heater is not deigned to heat such a large area.

Two options you can fit a heater in the rear that runs off the engine cooling system similar to the cab heater, can't remember the make but I'm sure Derek will be along soon with a comprehensive answer. The other is, if you have one of the modern Truma combi fan flued heaters these can be used whilst travelling providing you fit the Truma SecuMotion regulator.

 

Or if you don't want to spend any cash do what we do that is run the gas heating for 15-20 minutes before setting off, as the cab heater is not trying to heat a large area from cold it can usually maintain the temperature.

 

 

[Derek Uzzell]

pointy:

 

Taking lennyhb's suggestions in order...

 

1. Auxiliary blown-air heaters exploiting the vehicle-motor's cooling system can be obtained from CAK Tanks (www.caktanks.com). Cost of the heater-unit itself would be £150-£250 depending on the unit chosen, plus hoses, valves, wiring, etc. and fitting charges. This is probably the most satisfactory solution, but may prove difficult to implement retrospectively.

 

2. Swift marketed the Sundance 520 for quite a few years (it always helps if you provide the model-year). I've looked at a selection of current on-line adverts and noted that the internal layout seems to vary according to the model year. Whatever the layout, space-heating always seems to be via a convector-fire (probably a Truma product: possibly from Carver), perhaps with a blown-air capability, and installed towards the centre or rear of the motorhome's living-area.

 

Some Truma gas 'fires' are designed to be capable of being operated while the motorhome is being driven provided that the correct roof-mounted flue-outlet is fitted. You'd need to confirm exactly which heater you have and then take advice from Truma(UK) about the practicality/advisability of using it while travelling. As far as I'm aware, there are no general UK regulations forbidding use of a gas-heater in a motorhome while travelling in the UK, though other countries have different rules.

 

3. Revising your Sundance's gas system to include a specialised 'safety' regulator is probably a non-starter - I think your motorhome is likely to be too old for this alteration to be viable.

 

4. You could fit a small secondary air-heater, like a gas-fuelled Truma E-2400 or a diesel-fuelled Webasto or Eberspacher unit, but this would be expensive.

 

5. A Sundance 520 is pretty compact. The cab-heater on the Fiat base-vehicle never had a reputation for high heat output, but could sometimes respond to TLC, so it would be worth checking whether your cab-heater's current performance is below-par. If the cab-heater can be persuaded to function more efficiently, that may be sufficient for heating the rear of a small motorhome enough to avoid your daughter getting frost-bite. Depending on your motorhome's layout, it may also be practicable to hang a ceiling-to-floor curtain just behind where your daughter sits as that would contain the heat from the cab-heater within a smaller volume.

 

Otherwise, I think your daughter may need to keep her coat and hat on...

 

 

[dikyenfo]

I use a 12v heated blanket plugged into a self-fitted socket and it is big enough to fit round 2 adults never mind a child. Cost is reasonable and I got mine from Towsure but I think any accessory shop will stock them.

[Robinhood]

Child in the front, partner in the back? ;-)

If it is, (as I suspect) built on the previous Sevel (240 series) these suffered badly from draughts, particularly from the void into which the cab seatbelts retract (which appear to be open below the retractor mechanism), and around the cab doors (actually through the door skin!).

The combination of these can let an extraordinary amount of cold air in, especially when travelling, and the heater is probably already struggling without the further challenge.

It is common practice to minimise this by removing the cab pillar trim from around the seatbelts, and carefully blocking the void with sponge or foam rubber below the retracting mechanism (taking care of course to not interfere with said mechanism). The trim is then replaced. Put your hand agains the slot from which the belt emerges at the cab pillar, in wind, and test for draughts.

The cab door problem can be easily resolved by carefully duct taping over the "louvred slots" on the trailing end of the open cab door. These slots are designed to provide extraction through the door for the heating/ventilation system, and given the extra fixed ventilation in a motorcaravan, really aren't required. In fact, the extraction that occurs further back in the caravan body tends to cause air to come in through them, rather than go out!

It doesn't entirely fix the problem, but it can make a significant difference.

HTH

[terryW]

lennyhb - 2011-02-04 10:53 PM

 if you have one of the modern Truma combi fan flued heaters these can be used whilst travelling providing you fit the Truma SecuMotion regulator.

 

 

The Truma range is the Combi 4 and 6. Changing the regulator to take advantage of this was suggested to me by a gas installer but I when I got home and told my co-pilot I was informed that that "we" are not happy traveling with burning gas.

 

[lennyhb]

I can only agree with that, wouldn't do it myself but it is an option.

 

 

[Brian Kirby]

You would get more heat out of the heater if you ran it on "recirc", instead of (presumably) drawing in (cold) fresh air. 

The van has a large volume, so shortage of fresh air should not generally be a problem, but in any case, you have the control to hand, so can easily give it a blast of fresh as required.

[flicka]

Obtain a Heater matrix from Scrap yard with it’s Fan.

There should be a selection of sizes to choose from, so determine your prefered position sizes first.

Mount in the Motorhome habitation area. Or it maybe possible to mount a secondary heater under one of the Cab seats with the fan directing the air back into the habitation area. It maybe necessary to cut a underbed locker for the airflow outlet

Disconnect Engine to Cab Heater Feed Hose & replace with a longer Hose to feed the Secondary Heater & fit another longer Hose from the Secondary Heater back to feed the Cab Heater. (this will require two holes in the Motorhome floor to pass the Secondary Heater Hoses through)

Heater Hose can be bought in upto 20m coils.

Original Cab Heater return hose remains in place.

As the Secondary Heater will be mounted lower that the Cab Heater it should be selfventing. Routinging through the Cab Heater first can cause problems venting air from the extended system.

Run Cables to run the Secondary Heater Fan (with fuse & isolation switch) linked to the Cab Heater Fan preferably.

This method is used in Ambulances where the Secondary Heater is often mounted as far to the rear as possible.

But the further back you mount the secondary heater the more heat loss from the hose run.

[Brian Kirby]

flicka - 2011-02-05 9:24 PM ............. But the further back you mount the secondary heater the more heat loss from the hose run.

And due to that, and the heat extracted by the rear matrix, the cooler the cab heater will run!  Cold in front?  :-)

[747]

The first thing I would do is back flush your cooling system. The heater matrix may not be very efficient and I do know that they have had to be replaced completely by a number of people.

 

The suggestion to add another heater in the hab area should work quite well. My van has a heat exchanger fitted to warm up the back and it works well without detracting from the cab heating. It is simply a tee joint in the engine coooling circuit. There is an even better system which heats up the Alde wet heating system and also gives a tankful of hot water as well.

 

In my last van, I fitted a 6" diameter cooling fan to cool off the rear in summer. It should be possible to similarly fit something (maybe a bit smaller) to direct heat into the hab area.

 

It is possible to buy small dashtop plug in 12 volt fan heaters to rapidly demist a windscreen in winter. I suppose you could run one of those while on the move.

[Tony Jones]

Isn't anyone going to say "Welcome" to "pointy?"

 

Well I will then. Welcome to the madhouse "pointy," but as you can see there are a few sane voices among us.

 

'Fraid I can't be much help here - I read your title and was going to suggest thermal underpants!

Last time I had serious temperature problems in a van it was a T2 VW (aircooled), and that was the fornt as well! The only answer with them was flying boots.

[flicka]

Brian Kirby - 2011-02-06 3:16 PM

flicka - 2011-02-05 9:24 PM ............. But the further back you mount the secondary heater the more heat loss from the hose run.

And due to that, and the heat extracted by the rear matrix, the cooler the cab heater will run!  Cold in front?  :-)

Hi BrianWe had this system on a self-converted Bedford CF Ambulance back in the 70's & it worked fine. It's still in use today on many Ambulances

[Travelling Tyke]

Hello Flicka,

 

Now that is my kind of solution, thanks for this.....Not that we need it for the two of us.....walking thermals do come in handy.

 

[art338]

Not being a winter traveller the best suggestion seems to be the thermal blanket or jacket, many vehicles now have heated seats so why not clothing?

 

I read there is a clothing company called 12vclothing.com

 

art

[Derek Uzzell]

Unless pointy's cab-heater can be easily persuaded to produce more hot air output, I'm pretty sure dikyenfo's 12V heated blanket suggestion will be the simplest, cheapest, most effective solution.

 

12V blankets seem to be reasonable available in this country, though the asking-prices for (apparently) identical products vary considerably. The 12V power requirement appears to be no higher than 4Amps, so a dashboard-socket should be OK as a 12V-output source while travelling.

 

GOOGLE-ing on "blanket 12V uk" will retrieve various potential suppliers. This is a link to one:

 

http://www.discountelectronicsstore.co.uk/electronic_supplies/12v-heated-electric-blanket-12v-electric-blanket/

 

(www.12vclothing.com is a USA-based website)

[Brian Kirby]

flicka - 2011-02-06 9:45 PM

Brian Kirby - 2011-02-06 3:16 PM

flicka - 2011-02-05 9:24 PM ............. But the further back you mount the secondary heater the more heat loss from the hose run.

And due to that, and the heat extracted by the rear matrix, the cooler the cab heater will run!  Cold in front?  :-)

Hi Brian We had this system on a self-converted Bedford CF Ambulance back in the 70's & it worked fine. It's still in use today on many Ambulances

Yes, I accept that John, but the proposed installation is to a Fiat Ducato with a notoriously weak cab heater output.  Whether that weakness is due to poor delivery of hot water to the matrix, or a small, or inefficient matrix I know not.  All I am seeking to flag up is the possibility that the arrangement you describe, as I understand it, with the flow diverted first through the rear heater matrix down a long leg, and then back through an equally long leg before it gets to the cab heater matrix, is liable to considerably reduce the already inadequate heat output from the front matrix.  I understand the logic, and it would be fine with a cab heater that has adequate output, but with the Ducato heater I would have, unfounded on factor experience, doubts.  The only thing I can say with certainty, is that a Ducato is not a Bedford CF, so what works on the one, may possibly not work so well on the other.

I think this is possibly a Dave Newell type question!  :-)

[Dave Newell]

It is more normal when fitting a secondary engine coolant powered heater to tee the flow and returns into those of the original heater so that it is in parallel rather than series. In a series installation the water delivered to the cab heater will be significantly cooled from its run through long exposed pipes and the secondary heater. when piped in parallel both heaters get roughly similar temperatures of water.

 

D.

[flicka]

I understand your concern, Brian, especially if an additional Heater matrix where to be located at the very rear of the van.

 

The Swift Sundance 520 (AFAIA) has a forward Dinette & if the OT can locate the matrix under the rear facing seat, hose lengths could be kept to a minimum.

 

But considering Derek's suggestion of the 12v heater blanket, I guess my solution would not be cost effective.

[Robinhood]

Dave Newell - 2011-02-07 3:10 PM It is more normal when fitting a secondary engine coolant powered heater to tee the flow and returns into those of the original heater so that it is in parallel rather than series.  D.

Indeed, this is more normal. I've had both Rapido and Benimar 'vans on the 240 series Fiat with auxiliary heating provided in this way.

If anything, the rear heating was more efficient than the cab heating, and certainly raised the temperature throughout the 'van, not just the rear.

Both were, however, standard factory fit; retrofit would be entirely possible, but maybe a bit 'messy'.

Parts around £200 from CAK Tanks.

Edit:

Why can I see spelling mistakes on the post, but not on the preview :-S

[Mel B]

It appears that some people believe that when travelling in a motorhome they can have the same temperature that they have in a car, at best it would take a while to get to a warmish temperature, at worst it never will.

 

Some motorhomes have rear heaters or heating that can be left on whilst on the move, but this seems to be an expensive thing to 'after-fit', if it is even possible at all.

 

In a car in winter I would not expect to be able to travel without a coat on, so why in a motorhome?

 

A small quilt/throw to keep the tot warm with a 12v heated cushion may be the answer if it can be used 'safely' - these cost around £11 upwards.

 

[Robinhood]

Mel B - 2011-02-07 9:29 PM In a car in winter I would not expect to be able to travel without a coat on, so why in a motorhome?

By 'eck, I know things get cold in God's country, but If I had to wear my coat in the car in winter, I'm afraid it would be back to the dealers! :-S

[Brian Kirby]

Robinhood - 2011-02-07 9:42 PM

Mel B - 2011-02-07 9:29 PM In a car in winter I would not expect to be able to travel without a coat on, so why in a motorhome?

By 'eck, I know things get cold in God's country, but If I had to wear my coat in the car in winter, I'm afraid it would be back to the dealers! :-S

Abso-flippin'-lutely!  :-D

[Overdrive]

Our Rapido has an auxiliary heater matrix plumbed into the rear, with fan motor - it's brilliant.

 

I would agree with Robin Hood's comment that if anything its better than the cab heating, and due to the force of the fan we heat the whole van with it. Using the cab heater to keep the screen clear, and with the rear heater on fan position one it soon gets toasty!!

 

In Italian Summer heat, the rear fan is run without the heater to cool the interior to good effect.

 

Could you divert cab heating ducting to the nearest habitation blow heating outlet? One of our 1971 VWs had this arrangement.

 

David

 

 

 

 

[lennyhb]

Robinhood - 2011-02-07 9:42 PM

Mel B - 2011-02-07 9:29 PM In a car in winter I would not expect to be able to travel without a coat on, so why in a motorhome?

By 'eck, I know things get cold in God's country, but If I had to wear my coat in the car in winter, I'm afraid it would be back to the dealers! :-S

What decade are you living in Mel? My Morris Minor in the sixties didn't have a heater until I got one from the scrapie, since then I'm fairly sure all my cars have had heaters. Normal driving attire these days all year round is a short sleeve shirt might as well make use of the waste heat from the engine.