Propex vs Web/Eber

[Springsong]

This thread is really interesting, I just wish I had not read it.

Before I did I was firmly in the Webasto camp despite the rather heavy initial cost, but now I am leaning toward

the Propex, it sounds to me to be cheaper, cleaner, and quieter and as we already have gas on board not a problem.

Certainly this thread has made me think enough to go down to Norfolk Marine to get the griff on these heaters.

[Guest]

I've owned both Webasto and Propex heaters and my choice would definitely be Webasto. I've also experienced the diesel types when fitted as night heaters in various trucks I've driven over the years.

I fitted a Propex unit in a Hampton Safari which I previously owned and although satisfied with it at the time, mainly due to the reduced initial cost and the fact that you can buy a huge number of gas bottles with the amount of money saved at initial purchase, when compared to a Webasto unit the heat output was disappointing, and although it could warm the boat it never felt comfortably warm. I would also concur with the comments about on reaching the set temperature on the stat the unit shuts down completely and due to the hysteresis (big word from schooldays!) effect of the thermostats operation, the boat would get quite cold before the unit would re-ignite. I'd suggest until you experience a modern Webasto or Eberspacher unit, Propex will seem OK, but I don't believe it's the best heating you can fit.

The Webasto 3.5Kw unit fitted in my Bounty was new in her final few months of hire, just before she was sold to me and in six years of ownership it has never missed a beat. It always fires up quickly, without the requirement of the earlier types to start the engine to increase the voltage, burn's well until target temperature is reached, then shuts down to idling keeping the boat warmer than I'll ever need, with the minimum of noise. As a true winter boater if I don't get a shore power hook-up I have in the past run this all night, in which case I believe it uses approximately 5 litres of fuel over about 15 to 16 hours maintaining around 20C, and a Bounty is not well insulated! It does increase speed if doors have been opened but this is only for a short time.

About three years ago I did renew all of the ducting which was the original from when the boat was built and fully insulated all of it in the "Thinsulate" sleeving which makes a tremendous difference and is an addition I'd thoroughly recommend. I've also fitted a programmer so that it can be set to switch on when away from the boat for the evening, so that it's warm when you return.

This year I must have been feeling guilty, as I realised i'd never done anything at all to this heater, apart from switching it on and off when required, so on servicing the engine for the winter, I thought I'd better replace the small diesel filter fitted just before the heater unit. The filter element to my amazement was perfectly clean, from what I could tell, and it's replacement cost a whole £1 from Sonny Boulter! Fuel is taken from the main fuel tank and is drawn from a separate port on the output side of the water trap assembly.

[senator]

Springsong,

While I am firmly in he Propex camp I would conceed that if you have a high heating requirment then even the biggest Propex unit will struggle, 2.8kw of heat is fine for a fairly modern 30' sports boat but although I have only expirienced broads cruisers in the hire fleet, they do seem to be a fair bit more drafty than your average GRP sea boat, possibly due to the need to keep the sea out even when it is on top of the boat.

Ian

[Guest]

Diesel produces about 9 kwh per liter which is about 10p per kwh whereas butane is about 14 kwh per kg so about 50p per kw if you buy your camping gas from brooms. If your electric is reasonably in the marine then gas/electric makes sense.

Just serviced my eberspacher after a year running on high power only and it was very clean so no issues if used on high only.

Jonathan

[mbird]

Hmmm,

Just to throw a spanner in the works now, I had a good chat with Col after bumping into him at the Boat Show yesterday about this subject. I am going to do some investigation now, about the cost and availablility of second hand Webo's.

If I can get a second had unit and replace the burner and glow pin easily, for the same cost as a new Propex unit, then I think I will revert to the diesel option after all, possibly putting in a small secondary fuel tank that I can stick either paraffin or Derv into. I will have to check again, but I just don't think there's an easy way of tapping fuel from the main system, though I am on my way to the boat now to investigate this further. When putting in a separate tank, the BSSC guidline state that if the capacity is less than 27 litres, there is no need for any filling overflow arrangment, making installation a little more flexible.

Why are decisions about boats so flippin difficult? I was looking at cvhart plotters yesterday at the show, and the ranges are just bewildering

[RedRover]

I've owned both Webasto and Propex heaters and my choice would definitely be Webasto.

It does increase speed if doors have been opened but this is only for a short time.

About three years ago I did renew all of the ducting which was the original from when the boat was built and fully insulated all of it in the "Thinsulate" sleeving which makes a tremendous difference and is an addition I'd thoroughly recommend. I've also fitted a programmer so that it can be set to switch on when away from the boat for the evening, so that it's warm when you return.

Hi,Pete,fellow bounty owner here, I have a 3 year old (i think) Webo 3.5KW saw one the same at the boat show and was told as you say to start up full blast then turn it down to a lower temp to suit.,not a problem so far. it is not automaticly done if doors and windows are opened i just have an on/off switch. You said you fitted 'thinsulate sleeving' is that the webo's own make and is it expensive also is it easy to put on?

[RedRover]

Hmmm,

possibly putting in a small secondary fuel tank that I can stick either paraffin or Derv into. I will have to check again, but I just don't think there's an easy way of tapping fuel from the main system, When putting in a separate tank, the BSSC guidline state that if the capacity is less than 27 litres, there is no need for any filling overflow arrangment, making installation a little more flexible.

Hi,Mark,

Have you found out what the cost of a stainless tank would be it would be good to put in road diesel (cleaner burning) If i put in a seperate tank it would be easy as next to the main tank is a space for a new tank of about 10 gallons size with the pipe and pump next to it to reconnect.

[Guest]

Hi Barry,

i've just checked what records I have, which, along with my memory are a little sketchy that far back. To give you an idea, I can tell you that I got the materials from Keto Marine at Poole who were representing Webasto on their LBS stand at the time I visited in Jan 2008. I ordered the material and did the job in March 2008 and cost of the materials was £432.59 for everything on the output side of the heater. That includes new duct, insulation, 2 x Y pieces and 3 x outlets. When Silverline had fitted the new heater prior to sale of the boat in 2003 they'd simply connected it to the original ducting, which had seen much better days, so I replaced the lot with new parts. As far as I can remember the insulation is genuine Webasto, but without actually checking on board (and I don't live nearby, sadly!) I can't be 100% certain, but what I can confirm is the vast difference insulating the ducting makes to heat output at the outlets, especially the ones further away from the heater unit. obviously the amount of duct and insulation will depend on your actual installation, as many Bounty's are fitted out differently, and I believe yours is a 37ft one anyway. Fitting the insulation is job well worth doing though, as to whether it's easy, again, that depends on your own particular installation, but the type I fitted is sleeve and has to be threaded along the duct, rather than wrapped around it, so where it passes through bulkheads, the duct has to be pulled out and the size of the holes increased to allow for the extra diameter.

[mbird]

Right, I have just dropped an almighty clanger

I saw a Webasto unit on ebay last night for a very, very good price, considering it is new. I placed a bid and am currently winning. What I didn't realise is that the unit is petrol, not diesel , which I only spotted by chance when looking at the photos again, and noticing a pic of the original invoice mentioned "12V Petrol", which wasn't obvious until I enlarged the picture.

I have sent the seller a message asking him to retract my bid, but under ebay rules he has no obligation to do so. Assuming he won't cancel the bid for me, does anyone know what the physical difference between a petrol and diesel Airtop 2000 actually is? Could it be something simple like just a different fuel pump for example?

This could be an expensive cock-up

[Guest]

I don't know for sure, Mark, but the ignition system would be different due to the vast difference in volatility of the fuel, so I doubt it would just be a different pump. Due to how uncommon the petrol version is, I would think you'd need to contact Webasto to find out for sure.

[jimbo]

If you have explained to the seller that you didn't realise it was petrol at the time you bid, then surely they will understand.

[mbird]

If you have explained to the seller that you didn't realise it was petrol at the time you bid, then surely they will understand.

Panic over, as the guy has responded and is happy to cancel the bid as it was a genuine mistake. Thank heaven's there are still decent people about .... phew!

[Antares_9]

Just for the record there aren’t that many differences but they are important, on some models the burner pipe is smaller bore, later diesel models don’t have a flame sensor probe but the petrol ones still have one. But mostly the board is programmed differently, the pump timing (fuel volume) and differing timing in the start up and run down pulses. Common on VW campers and some other motorcaravans until quite recently and not certified for marine use in any circumstance. The last time I sourced a new complete kit, single outlet minus the skin fitting it was £740.00, I could ask my guy if the price has held if you like Mark.

[mbird]

The last time I sourced a new complete kit, single outlet minus the skin fitting it was £740.00, I could ask my guy if the price has held if you like Mark.

Well that is cheaper than the 2.8kw Propex, so would hold up on that side of the argument David. I would guess the skin fitting would be about £50? and the copper fuel pipe would be extra too, but other than that it would work out about the same.

I have now investigated further into the lazarette where I intend to fit the heating unit (whichever it is). There are two flow and two return fuel pipes passing through there, so I assume I could tee into one of the flow pipes without disrupting the flow of fuel to the engine would you think? By pure concidence the gas pipe also passes through this locker too, so it would seem both my fuel sources are in the right place

[Guest]

By pure concidence the gas pipe also passes through this locker too, so it would seem both my fuel sources are in the right place

Mark

by anychance would the previous owner have had a webasto unit already fitted but removed it before the boat went up for sale?

Jonny

[Antares_9]

Skin fitting about 50 on ebay as you say Mark, make certain it is for 22mm exhaust if using a 2000 series heater. You would also need some extra trunking and a "Y" or "T" piece but that's not going to come to more than another 50. As for the fuel take off I would only ever go with a standpipe or a tap off the pre filter, you could certainly fit an unequal copper T piece there with a compression fitting on the drop side to fit the 3/16" cunifer brake tube that is ideal as fuel pipe for these heaters. Shall I email my guy for a current quote?

[Jupes]

Hi Mark

I have absolutely no expertise to add to this interesting thread!

My only thought would be..... should/when you come to sell, will it be more attractive with a web/eber rather than propane to prospective buyers?

[mbird]

Mark

by anychance would the previous owner have had a webasto unit already fitted but removed it before the boat went up for sale?

Jonny

No mate, no holes where ducting went etc.

[Happy Jax 3]

Hi Mark

Looks like it is all going to plan.

Did you see the Airtop 2000 ST kits on ebay new, buy it now £779 ?

[Guest]

Hi Mark

Looks like it is all going to plan.

Did you see the Airtop 2000 ST kits on ebay new, buy it now £779 ?

Hi Col

i did have a look on ebay for a webba diesel heater & i did notice the one you mentioned there not cheap i think i would go for a recon rather than paying that.

Jonny

[mbird]

Hi Mark

Looks like it is all going to plan.

Did you see the Airtop 2000 ST kits on ebay new, buy it now £779 ?

Hi Col, yes David kindly pointed that one out. The problem with the ST model, according to JPC, is that is the vehicle version which has a different sensor, short wiring loom etc to the marine one and is not warranted by Webasto for fitting in a marine application. I tend to agree with David, though, that JPC are over-egging the differences as they want to flog me one, and the sensor can just be changed for an "S" model version for a few quid. JPC did advise against teeing into the fuel line though, due to the suction fom the engine when she's opened up draining the fuel line from the heater.

Those propex's are looking more attractive again, especially as there is even a tee fitting in the gas pipe in the lazarette that used to serve the fridge

[Guest]

PM Sent with details of a supplier of 2nd hand units, he also does refurbs!

[mbird]

PM Sent with details of a supplier of 2nd hand units, he also does refurbs!

Many thanks Dave.

[Guest]

does anybody know how efficient these propex hot air heater are & its 2kws hot enough for a boat how long will a bottle of gas last if were talking 13kg to 15kg.

there a lot cheaper than a diesel heater apparently maintenance well thats what they say

Jonny

[Antares_9]

does anybody know how efficient these propex hot air heater are & its 2kws hot enough for a boat how long will a bottle of gas last if were talking 13kg to 15kg.

there a lot cheaper than a diesel heater apparently maintenance well thats what they say

Jonny

They claim the 2kw model (not nearly enough to heat the cabin space on your boat) will run for just under 100hrs for a 13kg and just over 100hrs on a 15kg Jonny, so not long at all really.