Size of Webasto heater??

[tsadpt]

Hi everyone! We have a new Bavaria 36 on order, and are confused and befuddled regarding heater choices - we are certainly going to chose a Webasto hot air heater, installed in the sugar scoop (behind the aft cabin) - we will be using the forward cabin as our master cabin. We will be having 5 outlets in total (3 cabins, saloon, heads), although not all will be open at once - however, we do want to be able to get the whole boat warm when we are winter sailing, which we do a great deal, and SHMBO really feels the cold, but loves the winter sailing!

Should we go for a Airtop 3500 or a 5000? I know Opal install a 3500 if chosen from the options list, and this is what the dealer, Keto, reccomends, with insulated ducting. However, I have experience of a Bavaria 36 with an eberspatcher 4DL (without insulated ducting), and the heat output in the forecabin is just not adequate to melt an ice cream, let alone SHMBO! Another Webasto dealer, on the East coast, said we really needed the 5000. Webasto themselves are non-comittal, saying that both dealers are right - the 3500 is the right size for the boat, but we could go for the 5000 if we preferred....Aaagh!

The price difference between the 3500 and 5000 is only £238 + VAT. Should we go for the 5000, even though it will not be working at full power the whole time, or plump for the 3500, and hope it will do the job? Any other webasto owners out there with advice?

<hr width=100% size=1>

 

[andyball]

we've an eberspacher 3.5 in a 38' motorboat & I can see how with insulated ducting it'd just cope in the depths of a south-coast winter. But, even then, reckon on fore & aft being cooler that my wife cares for. We'll be upgrading/adding another one eventually.

I'd fit a 5kw version- less noise 'cos it's not on full chat for as long. & that bit in reserve.

For £238? ....easy choice for me.

<hr width=100% size=1>

 

[jackho]

I have an interest in your problem on two counts. Firstly I have a Bav.34 and have fitted a Propex Hot Air Heater - certainly not powerfull enough to heat a 36 especially in winter temps. Nevertheless I would make a point about insulated ducting - I prefer uninsulated as it runs underneath the bunks and through the battery compartment and electrical panel and maintains a better temperature differental helping to reduce condensation, especially in the colder weather.
To this end I would choose the larger heater and offset the cost by installing the uninsulated ducting.
I will be interested in your outcome as I am looking to trade up to a 36 possibly for next season.
Finally you should connect with the www.bavariaowners.org and test your options there. Hope this helps - Jackho

<hr width=100% size=1>

 

[tsadpt]

Thanks for your input Jackho - Regarding insulated or uninsulated ducting, I get your point about the ducting running underneath the bunk, but surely they are also running next to the bare hull, cooled by icy january waters on the other side, so any heat givn out by the ininsulated ducting would sureley go 95% to heating the hull and hence the Solent (!), and 5% to heating the bunks etc??

<hr width=100% size=1>

 

[tsadpt]

Hmm, thanks Andy

I think I am slowly leaning to your wife's point of view!!

<hr width=100% size=1>

 

[Talbot]

I have the Eberspacher airtronic d4 in a 9m catamaran (probably more space to heat than a 36' mono) It has 5 outlets (2 cabins, saloon, galley, navigation area) and is more than adequate for this use. If you must have webasto, go for the larger although check the power useage. I chose the eber as it has more fan speed settings thus will reduce fan speed (noise and electrical consumption) more frequently than either Webasto or mikuni. Keep the trunking as short as possible - sugest putting heater unit in engine room rather than scoops, and insulate it.

<hr width=100% size=1>

 

[lydiamight]

Having just had the Eberspacher unit on my Dehler 36 refurbished by the local dealer I was advised by him to try to run the unit at the maximum setting on the thermostat whenever possible--even if it meant opening hatches etc. His opinion was that the units are prone to "coking up" if run at less than maximum.

<hr width=100% size=1>

 

[robind]

Its easier/cheaper to turn it down than to increase the bthu output.
Regards
Rob


<hr width=100% size=1>

 

[bobnewbury]

We fitted a Webasto 3500 in a Victory 40 this year (centre cockpit, 43'). I've got 5 outlets, 1 in the aft cabin, one in the saloon, one in the foreward shower area and 2 in the wheelhouse.

The chappie at the London Boat show said that he reckoned the 3500 with insulated ducts would cope happily. He even promised (in writing) a free upgrade to the 5000 if the 3500 didn't cope.

I haven't had really cold enough weather to test it yet, but I post back when I have sufficient data.

Certainly it seems more than adequate at the moment and Keto have been exceptionally helpful.

<hr width=100% size=1>

 

[BlueChip]

I have a Webasto Airtop 5000 in a 37' sailboat, all the ducting is uninsulated

We have 6 outlets, 5 of them with shutters. They are in aft cabin & heads, two in the saloon fore and aft, forward cabin and forward heads. We sleep in the aft cabin so this is not a major problem for us.

We find that even with all the aft outlets closed there is very little airflow out of the forward cabin outlets and it would take a long time to get the fore cabin warm. On the other hand the aft cabin and aft heads are like toast and there is a blast of hot air through the outlets.

Saloon heating in deepest winter has been much better since we put another outlet in the saloon this evens out the heat, previously one end of the saloon was hot and the other end cold

I would say go for the higher model and work hard to get straight pipe runs as far as possible. In our boat the hot air pipe work has lots of bends and turns at the fwd end of the saloon leading into the forecabin. I think this is adding a lot of unnecessary restriction to the airflow.

Definitely insulate the ducting in the cockpit locker and selectively insulate other ducting depending on where it is running.


<hr width=100% size=1>

 

[jackho]

A now I don't think your going to heat the Solent - but perhaps the U value of a Bavaria is very poor!!!??? Anyway I'm told the water temp. is highest around November so maybe it might work in reverse.
I still think the technical issue is temp. diff. and condensation is the main issue with high air temp. in the cabins. In my case I dont mind the efficiency loss due to the uninsulated ducting as I believe the advantages outweigh the former.
Whatever your choice, enjoy your comfort and good sailing.

Jackho

<hr width=100% size=1>

 

[andyball]

warmer in November ?

I'm told the water temp. is highest around November


Eh? Not round here /forums/images/icons/smile.gif

<hr width=100% size=1>