Eberspacher DIY retro fit - 24ft GRP Cruiser

[Bantam_dave21]

Hi everyone,

 

I have a couple questions in relation to fitting eberspacher heaters in smaller older boats which I'm hoping the wealth of experience of the forum can assist with.

 

I've been planning through the winter months the fitment of an eberspacher diesel warm air system while out of the water in spring for our recent acquisition. We'd just like to extend our season a little, not into the depths of winter just so we can enjoy the nicer days of early autumn that would perhaps normally be a bit chilly overnight etc without some form of heating.

 

I have spent quite a bit of time going through BSS regs, advice and forums on here and think I have got a good idea of approximately where to fit which on a 24ft cruiser is erm interesting. The rear lockers are all but out of bounds - battery gases in the rear left, gas in the rear right and an outboard and its tank in the centre behind the transom. We have a tall hanging wardrobe which only accumulates general bits of everything so have allocated a spot there where I squeeze it in - the down side here will be the noise but int he absence of anywhere else to fit it I think this is my only option and don't want end up having move it at our next BSS examination.

 

I think I've got to the bottom of fire resistant hoses etc and proprietary connections rather than a bit o pipe pushed inside another 'bit o pipe'

 

What I think are my last questions (which may then bring more) are:

 

Is there any specific regulation or guidance on height from water line and distance from windows etc for exhaust outlet through the hull (my thinking here is as far away from both as possible) but if I'm physically restricted I'd like to ensure I don't encroach on any minimum distances.

 

I have purchased a plastic (polyprop?) tank of Eberspacher 10 litres I believe but can't ascertain if this is acceptable within BSS. BSS goes into lots of detail about filler caps of plastic tanks being acceptable rather than an external vent etc etc. I will probably as I get further into have a Mild Steel tank made to fit somewhere snug below the floor but keep to around 10-15 litres for space and to keep within guidance of BSS with a proper external filler but I'm a way off that - probably next season that part. Has anybody used one of these tanks? Had any problems with BSS etc?

 

Hopefully someone may be able to assist or share tips from fitting there own etc.

 

Many thanks,

Dave

[DaveC]

Before fitting any type of heater I suggest you get in place a decent charging system - I don't think your outboard will provide enough power to run an eber when the engine is not running. No experience of gas heating but that MIGHT be the way to go.

 

 

Dave

[NMEA]

The tank at 10l is fine for BSS, the major issue you have is that you will be installing it on a petrol boat and that scenario requires careful planning above and beyond the normal install, in fact for quite some time installing on a petrol boat was right out, so to speak for a petrol boat, still at least it's a OB not an inboard. The considerations are manifold so the best I could advice is to send you a copy of the Eberspacher marine install manual along with the petrol boat supplement which is a very useful document. A small 2kw is all you will need on a 24 footer. PM me with an email address if you would like me to send you a PDF of the manual. One point I should point out, a small craft with very limited battery capacity needs a proper marine spec blown air heater, the vehicle ones idle state is the fan still running whilst the marine ones are zero consumption on idle state, you could of course increase the battery capacity and charging regime to compensate as second hand marine units are very scarce and new ones are a premium price over vehicle type.

Edited February 7, 2016 by NMEA

[Arthur Brown]

Great info from NMEA

 

Remember that an eber (and I expect Weba and Mik...) will draw lots of amps on start up and some amps all the time so a well charged battery in good condition is essential, as is a very good charging regime. Remember that you will need most heating in the winter when solar doesn't contribute much to the battery state.

 

As a starter guess, assume that you will need 25A for two minutes to start the heater and 4a continuously to run it. The battery and wiring must be good enough to supply that 25A without significant voltage drop (or an eber will malfunction and maybe lock out and need resetting).

[WotEver]

As a starter guess, assume that you will need 25A for two minutes to start the heater and 4a continuously to run it.

So that's around 5Ah for one hour's heating.

[NMEA]

So that's around 5Ah for one hour's heating.

That's old technology coil wound glow plugs for you! and why I love Webos with the ceramic glow pin technology, on my test bed the pin takes about 12a for a few seconds almost immediately reducing to about 6 for 45 seconds or so and then drops out, even during that time the current is pulsed so reducing the consumption, on a Webo suited to a 24 footer (AT2000ST or STC) it would then pull about 2.5 amps for about an hour then reducing to around 1.

[Bantam_dave21]

The tank at 10l is fine for BSS, the major issue you have is that you will be installing it on a petrol boat and that scenario requires careful planning above and beyond the normal install, in fact for quite some time installing on a petrol boat was right out, so to speak for a petrol boat, still at least it's a OB not an inboard. The considerations are manifold so the best I could advice is to send you a copy of the Eberspacher marine install manual along with the petrol boat supplement which is a very useful document. A small 2kw is all you will need on a 24 footer. PM me with an email address if you would like me to send you a PDF of the manual. One point I should point out, a small craft with very limited battery capacity needs a proper marine spec blown air heater, the vehicle ones idle state is the fan still running whilst the marine ones are zero consumption on idle state, you could of course increase the battery capacity and charging regime to compensate as second hand marine units are very scarce and new ones are a premium price over vehicle type.

Hi NMEA,

 

thank you for the reply, I was quite concerned ref the tank as there was no clear guidance on plastic tanks and all the other regs ref fire resistance etc were worrying. Thank you for your kind offer of the install manual which I'd like to accept PM will follow with my email.

 

I had considered gas heating but with all the same safety issues as a diesel heater - any intake of combustable vapour etc...and the result would be disaster I went for the lower running current of the diesel and hopefully a more manageable fuel supply - my locker is very small and 2 x 4kg butane bottles is a squeeze.

 

thanks,

Dave

[Bantam_dave21]

I have prepared my electrical system for the change - hopefully....how I get on I'm not sure, but hopefully as we won't generally cruise in the winter the lack of solar should not be too much issue.

 

I have 4 x large leisure batteries purely for the 'house' system which I keep in two separate banks of 2 - one in use, the other disconnected and I alternate them. A single engine starter battery to hopefully reduce my risk of ever being stranded. We have 300w of solar through a split charge solar controller, the OB charges around 6A at best, we are reasonable electric frugal...only a small coolbox (we have a compressor fridge but running is around 5-6A so generally use the box) 2 lights in the cabin LED and 1 in the wheel house also LED. We don't cruise at night but have changed all external lights inc anchor light for LED.

 

We have an eberspacher D1LC and haven't clipped on while the units running but the specs suggest 20A for 50 seconds starting and between 0.8 and 1.6 running assuming we're not on the high setting which is around 2.4A so we're going to see how we go in terms of usage. We generally only use the boat at weekends and is on shore power through the week so hoping the battery system will cope with it.

 

Thanks NMEA I genuinely hadn't realised there were specific marine eberspachers I will have to keep an eye on the fan staying running would also drag cold air in too if it was piped that way - still not sure if to re circ the pipework as the air outlets will be quite low in the boat so any gas leak would be pulling through the unit although not on the combustion side this is being piped from outside. I do have a broken webasto air top too but was just about given the eberspacher so was kinda led down this path.

 

Cheers,
Dave

[TheBiscuits]

Hi NMEA,

 

thank you for the reply, I was quite concerned ref the tank as there was no clear guidance on plastic tanks and all the other regs ref fire resistance etc were worrying. Thank you for your kind offer of the install manual which I'd like to accept PM will follow with my email.

Excellent replies from NMEA, so another greenie for him.

 

I have the Webasto Air Top 2000ST, and confirm NMEAs electrical usage figures.

 

I had considered gas heating but with all the same safety issues as a diesel heater - any intake of combustable vapour etc...and the result would be disaster I went for the lower running current of the diesel and hopefully a more manageable fuel supply - my locker is very small and 2 x 4kg butane bottles is a squeeze.

 

thanks,

Dave

 

That's exactly the calculation I made when looking at a propex for a Nauticus 27 - only using the tiny bottles makes gas cost a fortune if you actually want to use the heating. Having a diesel tank already on board helped sway it a bit though

Edited February 7, 2016 by TheBiscuits

[WotEver]

I have 4 x large leisure batteries purely for the 'house' system which I keep in two separate banks of 2 - one in use, the other disconnected and I alternate them.

What's your reasoning behind that, Dave?

 

Tony

[Bantam_dave21]

What's your reasoning behind that, Dave?

 

Tony

 

Hi Tony,

 

I once had a poor experience with a battery charger failing to realise I had a battery down in a bank, a few hours later I checked on the batteries (I've seen a battery blow in my work so am always checking them) the bad battery was literally about to blow. Bulging sides and a huge acid smell and very hot in locker. The charger had I'm guessing seen the bank voltage wasn't rising so had been giving it some welly....I replaced the charger with a CTek unit but it couldn't handle the overall Ah of the 4 batteries...

 

I keep change them over so I can keep the charger size down....I might be doing it wrong and should probably have a particular charger or set up but did it in a way I felt from experience was safer and more comfortable with. Getting one larger connected in parallel bank is also on my list. And I'm still learning the better ways of certain things

 

Cheers,

Dave

Excellent replies from NMEA, so another greenie for him.

 

I have the Webasto Air Top 2000ST, and confirm NMEAs electrical usage figures.

 

 

 

That's exactly the calculation I made when looking at a propex for a Nauticus 27 - only using the tiny bottles makes gas cost a fortune if you actually want to use the heating. Having a diesel tank already on board helped sway it a bit though

 

I'd have given 2 greenies if it would let me - nice to get answers to questions, proper answers with pragmatism thrown in.

 

How did you find your install in a nautilus? I imagine similar space constraints to my 24 footer....

 

 

edit : Ctek 'couldn't handle....'

Edited February 7, 2016 by Bantam_dave21

[WotEver]

 

Hi Tony,

 

I once had a poor experience with a battery charger failing to realise I had a battery down in a bank, a few hours later I checked on the batteries (I've seen a battery blow in my work so am always checking them) the bad battery was literally about to blow. Bulging sides and a huge acid smell and very hot in locker. The charger had I'm guessing seen the bank voltage wasn't rising so had been giving it some welly....I replaced the charger with a CTek unit but it could handle the overall Ah of the 4 batteries...

 

I keep change them over so I can keep the charger size down....I might be doing it wrong and should probably have a particular charger or set up but did it in a way I felt from experience was safer and more comfortable with. Getting one larger connected in parallel bank is also on my list. And I'm still learning the better ways of certain things

 

Cheers,

Dave.

Fair enough but have a read of this: http://www.smartgauge.co.uk/splitting.html

 

Tony

[Bantam_dave21]

Fair enough but have a read of this: http://www.smartgauge.co.uk/splitting.html

 

Tony

Really useful link, thanks Tony...

[Arthur Brown]

The issue with start up current (whether it's 25 or 12 amps!) is that the battery must be capable of supplying the start current and the cables and distance and connectors must be suited for that duty or else the heater will make failed attempts to start then lock out in the software, needing a full battery and the right controller to reset it.

 

Never neglect that 4amps over a 18 hour day is the usable electricity in one typical 110AH battery. You really do have to run a generator daily to keep up with an eber/Mik/Web unless you have a huge solar array, or shoreline.

[Bantam_dave21]

Hiya,

 

Thanks Everyone for your assistance so far. I've still not come across any regs for the exhaust outlet.

 

I'm an electrical engineer by day and have pretty much sussed the cable sizes, volt drop etc. The batteries are well up to it, they're all quite new and get thoroughly replenished at the end of every weekend. I'm not planning to use the eber for hours and days on end, I only use the boat at weekends and from experience this Autumn I'm reckoning the odd hour here and there when we get caught out with an unexpected cold night.

 

I've now have a marine install manual - thanks NMEA.

 

Cheers,

Dave