How long can I run my Eberspacher for?

[matt1]

Electrickery not my strong suit but despite this I will shortly be wiring in an Easystart Web controller so I can switch my heater on remotely (the boat is on a mid stream mooring through the winter). Typically I would run it for an hour or two periodically. The quesition is, how many times a month could I run it for whilst still maintaining the battery charge?

I have a 110w Solar panel, which between Oct - March generally gives a total of 10kwh charge. (My spreadsheet says 0.059wh per day on average)

Eberspacher quote the D4plus using;
Start. 100
Max Power. 55
High Power. 30
Medium. 16
Low. 7

(Watts)

I'm sure this would make a good GCSE maths of Science question ;-)

Thx

 

[Slowboat35]

Oops! Can't delete.

 

[mattnj]

I don't think you'll have much problem with a 110w panel

 

[cpedw]

I would sack the question setter. According to the back of my fag packet, 10kWh over 6 months (~180 days) is good for about 55Wh per day.
On that basis, neglecting startup as it's (hopefully) short compared to the run time and assuming medium power then 2 hours would conume 32Wh so running daily for 2 hours should be feasible. 1 hour daily at max power would be on the edge of sustainable.

 

[matt1]

I would sack the question setter. According to the back of my fag packet, 10kWh over 6 months (~180 days) is good for about 55Wh per day.
On that basis, neglecting startup as it's (hopefully) short compared to the run time and assuming medium power then 2 hours would conume 32Wh so running daily for 2 hours should be feasible. 1 hour daily at max power would be on the edge of sustainable.

Well I did start by saying this wasn't my strong suit

My 10kwh total comes from the victron MPPT showing "lifetime consumption" as 34Kwh on the 6th Oct and 44Kwh on the 22 March

 

[mattnj]

Well I did start by saying this wasn't my strong suit

My 10kwh total comes from the victron MPPT showing "lifetime consumption" as 34Kwh on the 6th Oct and 44Kwh on the 22 March

You need to consider.....if you're not using the power.....the solar controller will only show the power needed to keep battery topped up...
If you start using power...
The controller will show the 110w panel "generated" more...

Hope that makes sense.

 

[jwfrary]

Presumably theres also theres a parasitic draw of the controller to consider and periods of low yield.

 

[Ian_Rob]

Electrickery not my strong suit but despite this I will shortly be wiring in an Easystart Web controller so I can switch my heater on remotely (the boat is on a mid stream mooring through the winter). Typically I would run it for an hour or two periodically.

As an aside, I asked a similar question 8 years or so ago. I seem to recall that the consensus then was that it isn’t that useful/sensible to periodically run a heater during the winter as described. The argument against it was that whilst it will take the chill off, it is also likely to pull-in more moisture laden air into the boat.

 

[DeepKeel]

As an aside, I asked a similar question 8 years or so ago. I seem to recall that the consensus then was that it isn’t that useful/sensible to periodically run a heater during the winter as described. The argument against it was that whilst it will take the chill off, it is also likely to pull-in more moisture laden air into the boat.

In the best tradition of answering the question that I think you should have asked rather than the question you actually asked ;-)

I am inclined to agree. In my experience very simple , low power consumption and low cost extraction fans, dramatically reduce the mustiness and mould in a closed-up boat, while I suspect that a heater would just create a greenhouse effect. With that much solar, you could leave them running 24/7 without a problem - with appropriate circuit protection of course.

 

[Wansworth]

Ventilation not heat

 

[Ian_Rob]

In the best tradition of answering the question that I think you should have asked rather than the question you actually asked ;-

?……?

 

[Wing Mark]

As an aside, I asked a similar question 8 years or so ago. I seem to recall that the consensus then was that it isn’t that useful/sensible to periodically run a heater during the winter as described. The argument against it was that whilst it will take the chill off, it is also likely to pull-in more moisture laden air into the boat.

Presumably you don't use the heater in your car, for the same reason?

 

[Wing Mark]

Electrickery not my strong suit but despite this I will shortly be wiring in an Easystart Web controller so I can switch my heater on remotely (the boat is on a mid stream mooring through the winter). Typically I would run it for an hour or two periodically. The quesition is, how many times a month could I run it for whilst still maintaining the battery charge?

I have a 110w Solar panel, which between Oct - March generally gives a total of 10kwh charge. (My spreadsheet says 0.059wh per day on average)

Eberspacher quote the D4plus using;
Start. 100
Max Power. 55
High Power. 30
Medium. 16
Low. 7

(Watts)

I'm sure this would make a good GCSE maths of Science question ;-)

Thx

10kwh over 150 days is about 66wh per day.
Assume it takes 1 minute to start, that's 100W x 1 min or 1.66 Wh
If it runs continuously on medium for an hour that's another 16Wh
If it starts and stops a lot due to getting hot, it will use more starting than it does running.

I reckon you need to allow for a few dull days in a row not use the average.
I would want some airflow out of the boat to let the warm moist air out.

If you aren't letting the rain in, it should not take a lot. I have a double garage/workshop, with a slight draught around the door.
I find running a 2kW fan heater for an hour a couple of evening each week keeps the humidity down quite effectively.

But if I've put a load of wet stuff in there, I find more ventilation is needed, or fire up the dehumidifier, and/or run the heater for a lot longer.

Can the web controller give you feedback on the battery volts and humidity?

 

[Ian_Rob]

Presumably you don't use the heater in your car, for the same reason?

.

Well they aren’t really equivalent situations are they. It is not exactly clear what the OP‘s intention is but seemingly it is to put periodic heat into a boat that is on a swinging mooring, during the winter, remotely controlling when the heat comes on. Being afloat, the boat is less likely to be affected by frost anyway so presumably the concern is mainly damp. When we moved to a swinging mooring 8 years ago, it crossed my mind that running the heater periodically might give some useful warmth but when I spoke to Webasto about the idea they advised that it wasn’t a suitable (or safe) substitute for a tube heater or dehumidifier.

 

[Wing Mark]

.

Well they aren’t really equivalent situations are they. It is not exactly clear what the OP‘s intention is but seemingly it is to put periodic heat into a boat that is on a swinging mooring, during the winter, remotely controlling when the heat comes on. Being afloat, the boat is less likely to be affected by frost anyway so presumably the concern is mainly damp. When we moved to a swinging mooring 8 years ago, it crossed my mind that running the heater periodically might give some useful warmth but when I spoke to Webasto about the idea they advised that it wasn’t a suitable (or safe) substitute for a tube heater or dehumidifier.

When I get my boat, it will have a hot air heater on it.
I'd hope that it's pretty safe if properly installed.

Personally I will be aiming to visit the boat often enough , so I won't need the heater to run when I'm not there.
I don't even like leaving my dinghy un-checked for much more than a week.
I suppose there are quite a few things which could go wrong if you leave the boat for a month and keep firing up the heater.

Tube heaters and dehumidifiers probably are not a suitable substitute for an eberspacher on a mid-river mooring.

 

[Ian_Rob]

We never leave our Webasto running when we are not aboard and so far as I recall, the manufacture’s instructions specifically say that it shouldn’t be left unattended. In 12 years we have only ever had one issue with it when someone inadvertently blocked the exhaust by dangling a fender from the stern rail.

I would hate to have it running when no one is there. Clearing the boat of fabric and paper and reasonable ventilation is the key.

 

[matt1]

Thanks everyone- my last boat had x3 solar deck vents - 2 on extract and 1 pushing air in. This seemed to keep the air moving nicely & I never had a problem with damp. It's essentially air movement I'm trying to establish. I haven't yet decided whether to use the Eber in ventilate mode (obviously less current draw) or heat, but wanted to at least get a feel for what is theoretically possible in heat mode given the power limitations.

That said, the main reason for installing the easyweb is so that it's warm (& conducive to doing jobs!) when I check on her in the winter. This will allow me to switch the heater on before I even set off to check on her ;-)

I don't believe the easyweb will give me humidity, but it does give battery voltage. Whether this is continuous or just whilst in operation I'm not sure. I think I can set voltage parameters under which it will / won't operate.