Auxiliary heater confusion

[Roy C]

There is a lot of confusion in reviews and amongst untrained MB dealers with regard to the auxiliary water heater. Some people buying the MP have unfortunately been caught out and have not got what they expected so I thought it would be useful to have a separate thread explaining the (expensive) auxiliary heater options to aid those buying.

There are two auxiliary heaters options on the MP: a hot water heater and a warm air heater. Both are powered by fuel in the MP's tank both have remote controls and both can heat the interior of the van but there are some important differences. First of all, contrary to some information in on-line reviews and given by some MB dealers, the hot water heater does not heat the water supplied to the sink taps or to the shower attachment.

Auxiliary water heater - uses fuel to heat the engine coolant, which serves two purposes:
1) to complement the vehicle climate control system with a heat boost to heat the interior of the vehicle but only for a maximum of 50 minutes
2) pre-heats the engine coolant to reduce wear and tear on the engine and save fuel on start-up - useful in cold winter climates

Auxiliary warm air heater - uses fuel to heat the vehicle interior but unlike the water heater it can be run continuously to maintain a steady temperature. It does not pre-heat the engine coolant.

I hope this helps someone avoid an expensive mistake.

 

[BabaJen]

A helpful clarification Roy that should help many.

The coolant heating is terribly nice but for most would probably be redundant with the auxiliary interior heater. 10 minutes on even the coldest of days and the interior is nice and warm, and if like me have it come on a few times during s frosty night, no frozen windscreen or misting up when you get in.

A shame that both MP and VW refer to the two heaters in terms bound to confuse.

 

[WILLH]

Does anyone know what the additional heat exchanger for the rear does or how more effective it is than the standard system?

 

[James G]

I'm looking to buy an MP soon. I've understood the posts about the options of auxiliary air heater and water heaters but what is the electrical auxiliary heater that comes as standard? Does it only work off a hook up? Its all rather confusing!

 

[Toby]

Hello - first post, so be gentle...

I'm going to buy a Marco Polo soon. Of the few that are for sale on the approved Merc list only two have the aux air heater, and the cheapest of these is one of the priciest in the list. So, if this heater is a must-have for me, and I don't want to wait for a factory order, I need to look at the aftermarket aux air heater fitting options. I've had some prices, and they all come in way below the merc list price for the heater. However, I'm looking for an aftermarket supplier/installer who can ideally hook up the electrics to the control console. I've read of one user having his done in the Basque country, but I was hoping for something a little closer to the New Forest...

all comments welcome.

regards
Toby.

 

[DWB]

Hi Toby,
What are you looking for spec wise, Sir? Just that I bought a 250 with all the bells and whistles which has 260 miles on it now and may have to move with work to UAE and don`t really want to put it in storage.

 

[Toby]

I've finally found taken the plunge, and will take delivery of my MP on Monday. Despite the weather it has neither the aux water nor the aux air heater. Probably why I can afford it. Thus it's first stop is a local camper specialist to have an aux air heater fitted - MB didn't want to know about fitting one at it's dealership. So my questions are:

a) has anyone any experience with retrofitting aux air heater on an MP? make? position? control unit? cost?
b) any recommendations on the south coast for a specialist to perform this?

I've found a firm near Poole, and at a bit over £1k with a timer this seems like a good deal, at least compared to list price on a factory fit. I'd like to make sure that it is fitted as unobtrusively as possible, and so would also like to know where the factory fitted heater is positioned, and what make it is.

Any information gratefully received.

 

[davidk]

The factory diesel heater on the old Viano MP is a Webasto, underneath the (LHD) driver’s seat

 

[Toby]

The factory diesel heater on the old Viano MP is a Webasto, underneath the (LHD) driver’s seat

Thank you, David. Does the old Viano MP have swivel front seats? I.e. is there any reason why the new MP wouldn't have the heater in the same place? I've asked MB Poole to give me the diagram from their workshop manual to help the folk at the camper converters (Uberbus), but so far MB are not cooperating.

 

[davidk]

Yes the front seats both swivel.

I'd have thought the diesel heater in the new one would be the same but I don't know for certain

 

[James G]

the auxiliary hot air heater is underneath the passenger front swivel seat

 

[Simon Fletcher]

Just wondering if the auxiliary water heater runs for a maximum of 50 minutes is there any reason why it cant be set to run for another 50 minutes later on in the day/night?

Not an owner yet so not sure how the auxiliary water heater is turned on, via switch or timer???

 

[mptripsaway]

Just wondering if the auxiliary water heater runs for a maximum of 50 minutes is there any reason why it cant be set to run for another 50 minutes later on in the day/night?

Not an owner yet so not sure how the auxiliary water heater is turned on, via switch or timer???

Have a read of the "Heating" thread in technical forum and all will become clear.

 

[Simon Fletcher]

Thanks for information, will take a look

 

[Theo Har]

Hi Toby,
What are you looking for spec wise, Sir? Just that I bought a 250 with all the bells and whistles which has 260 miles on it now and may have to move with work to UAE and don`t really want to put it in storage.

Hi there, Have you sold your V250? I'm on the market for one.

 

[DWB]

Hi there, Have you sold your V250? I'm on the market for one.

Hi Theo,
No, Sir but have decided to keep it for now, Sorry.

 

[Mike S]

There is a lot of confusion in reviews and amongst untrained MB dealers with regard to the auxiliary water heater. Some people buying the MP have unfortunately been caught out and have not got what they expected so I thought it would be useful to have a separate thread explaining the (expensive) auxiliary heater options to aid those buying.

There are two auxiliary heaters options on the MP: a hot water heater and a warm air heater. Both are powered by fuel in the MP's tank both have remote controls and both can heat the interior of the van but there are some important differences. First of all, contrary to some information in on-line reviews and given by some MB dealers, the hot water heater does not heat the water supplied to the sink taps or to the shower attachment.

Auxiliary water heater - uses fuel to heat the engine coolant, which serves two purposes:
1) to complement the vehicle climate control system with a heat boost to heat the interior of the vehicle but only for a maximum of 50 minutes
2) pre-heats the engine coolant to reduce wear and tear on the engine and save fuel on start-up - useful in cold winter climates

Auxiliary warm air heater - uses fuel to heat the vehicle interior but unlike the water heater it can be run continuously to maintain a steady temperature. It does not pre-heat the engine coolant.

I hope this helps someone avoid an expensive mistake.

 

[Mike S]

Hi Roy all very useful info and your certainly right about MB dealers knowing little about the Marco Polo !!
We have just purchased and still slightly confused as everything suggests that there is a standard warm air heater (Not the additional ones you mention than run off the diesel)
The control panel even has the on off settings for it but nothing seems to operate when on ? Even when on hookup ?

Mike

 

[Roy C]

Hi Mike,

The standard heater (climate control) is the one that operates when the vehicle engine is running, i.e. pretty much like every car / van has. However I believe you can set this to run off residual engine heat. This heater is controlled via the multimedia controls via the REST button. The auxiliary heaters can be controlled via the central control panel but if you don’t have either then I’m not sure if the option still appears on the LCD panel menu even though it is non-functional. I have the auxiliary warm air heater so I have the menu option and, of course, it is therefore operational. Hopefully there is someone on here that doesn’t have either of the auxiliary heaters who can confirm my theory for you.

 

[Mark E Smith]

I dont have either but the lcd control panel displays a heater icon which is of no use !