# Heating using the Inverter ?



## CaptainBligh (Jan 18, 2008)

Hi All 

Whilst staying on site at Livigno in Italy I tried to use a 1100 watt heater which just tripped the electric. So I thought I would use the 1500W inverter to power it. All seemed OK until the heater started to smell of burning even though it stated it had an overheat cut out. Do you think it was because my inverter voltage was fluctuating ? Or was it an electrical cardinal sin to use the inverter and heater this way ? 

Best Regards Captain Bligh :brave:


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## sallytrafic (Jan 17, 2006)

Was it a fan heater? Fan motors don't like modified sine wave inverters.

As to a cardinal sin how much battery do you have? 1100W is 90Amps at 12V


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## trevorf (May 16, 2005)

Are you sure it was the heater smelling of burning? As Frank said 90A is a lot of current, it could have been your inverter wiring starting to melt 8O 8O 

Trevor


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## CaptainBligh (Jan 18, 2008)

sallytrafic said:


> Was it a fan heater? Fan motors don't like modified sine wave inverters.
> 
> As to a cardinal sin how much battery do you have? 1100W is 90Amps at 12V


Yes it's a ceramic fan heater so I was probably burning out the fan. As for battery I have 3 X 125W batteries.

Captain Bligh :brave:


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## CliveMott (Mar 10, 2008)

Light the bl...y gas for Christ sake!

Using the battery to provide habitation heating is pure madness.


In the "good old days" we used to light the cooker to warm the van up, but all the windows soon misted up.


C.


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## CaptainBligh (Jan 18, 2008)

CliveMott said:


> Light the bl...y gas for Christ sake!
> 
> Using the battery to provide habitation heating is pure madness.
> 
> ...


Appreciate your comments but I was running out of Gas and the nearest LPG Garage was 2 hrs away. The campsite owner was not really providing enough amperage for a wintersports destination. I live and learn ! 
I
Captain Bligh :brave:


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## dwwwuk (Dec 31, 2005)

Interesting topic... 

Is there a definative 'no-no' list for modified sine inverters (fan heaters being one of them)?

I was thinking about purchasing an inverter to use for occasional microwave / boiling an 850W kettle (which in both cases are 3-4 minute tasks generally) - does this make sense or am I daft thinking about it? What size inverter is recommended for an 800W microwave? should I be looking at double - i.e. around 1.6KW continuous or would 1KW be fine?

I take it Truma heaters (blown air) would not be good on an inverter or do these run on 12V (the fans)? (not thinking about it just curious and on topic)

Kind Regards,

David.


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## iconnor (Nov 27, 2007)

*Inverter/heater*

Yes the Truma fan is 12v.

You guys must have some battery banks to even consider this stuff!


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## spindrifter (Nov 14, 2006)

Hi Capt'n

Basic questions you have to ask are: 

a/ Does your battery/12 volt supply have enough energy to keep your inverter on long enough to heat/cook or power your other 240 volt appliances?

b/ Can you replenish your 12 volt battery bank after you've drained them powering your inverter.

If not - it is almost a cardinal sin!!

Cheers

David


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## b16duv (Feb 14, 2006)

spindrifter said:


> Hi Capt'n
> 
> b/ Can you replenish your 12 volt battery bank after you've drained them powering your inverter.
> 
> David


I always leave my battery charger on when using the inverter - if the inverter is on anyway, might as well recharge the batteries?

And as a by product, there is usually lots of heat from inverter and charger as well so no need for a fan heater!

Sorted.

David


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## spindrifter (Nov 14, 2006)

Yes. But is Cap't on EHU. 

I read the question that he was not on EHU. 

If on EHU why use an inverter?

Cheers

David


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## olive (Feb 5, 2008)

David[/quote]

I always leave my battery charger on when using the inverter - if the inverter is on anyway, might as well recharge the batteries?

[/quote]

Laugh!!! I don't think my knickers will ever dry


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## sallytrafic (Jan 17, 2006)

When you only have a limited supply hook up say 4A using a battery through an inverter to heat can just about be justified.

An example

I designed a lighthouse installation that was primarily run by solar.

When men went on station by helicopter they could only take a 4kVA genny. This wasn't enough to cook with, heat showers and heat the sleeping accommodation. 

By powering the mains distribution from batteries using a large inverter the genny could be run 24/7 to charge the battery whilst the batteries coped with the peak loads. At the telemetry base station the battery could be monitored to ensure that the men on station put as much in as they took out. (We didn't proceed with the design as the operators decided to leave a bigger genny on station)


To translate this to motorhome usage would require only that all the ac be fed from inverters but using deep cycle traction batteries instead of leisure ones. The battery charger would be sized to use all the 4A hookup which would give 22kWhr in a day. I wouldn't do it on less than an RV sized installation because of the battery size but they normally carry generators. As I said almost justified


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## b16duv (Feb 14, 2006)

olive said:


> Laugh!!! I don't think my knickers will ever dry


Hang them over the inverter and they'll be dry in no time!


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## pieterv (Feb 3, 2009)

CliveMott said:


> In the "good old days" we used to light the cooker to warm the van up, but all the windows soon misted up.
> 
> C.


Windows misting up is the least of your worries. CO poisening is a distinct possibility when you heat with the cooker.


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## karlb (Feb 22, 2009)

pieterv said:


> CliveMott said:
> 
> 
> > In the "good old days" we used to light the cooker to warm the van up, but all the windows soon misted up.
> ...


errr ok, so what happens when you cook with the cooker?


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## spindrifter (Nov 14, 2006)

Open the windows - Oh b*****r it's drafty now!


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## TR5 (Jun 6, 2007)

pieterv said:


> CliveMott said:
> 
> 
> > In the "good old days" we used to light the cooker to warm the van up, but all the windows soon misted up.
> ...


Providing there is complete combustion, there will be no CO produced.

However, without good ventilation, and in the longer term, burnt gases will not be very pleasant to breathe in. Also, poor ventilation will cause reducing oxygen levels within the van, combustion will not be complete, and therefore would evntually start producing CO.

Short periods of using the cooker for providing heat will not be a problem, provided the cooker itself is working correctly, and fixed ventilation holes are clear.


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## 121696 (Mar 24, 2009)

*Re; Inverter For Kettle/Microwave*

Hi David (dwwwuk)

I would agree with the others leave the heater well alone.

But with regards to a 800w microwave and kettle, I would suggest a 1800w inveter. This is a common output now and will cope quite happily with that load.

As previously mentioned, replacing the battery amps is your problem. Do you have solar panels? If you do this will obviously help but with the amount of power being taken out (daily) you really do need to have reasonable size panel to make the system work effectively.

If you are thinking off purchasing solar panels, then a system of at least 120w would be needed to give you daily usage (within reason) during the better 6 months of the year, assuming you are stationary for around 4-7 days. And a battery bank of at least 220Ah. Any longer and you really need to consider more solar and/or additional charging methods i.e. battery-to-battery charger or fuel cells!

We installed a system of 190w of solar, 3 x 125Ah Elecsol batteries and use kettels. toaster and microwave (700w) and never have a problem during. In the winter we simply monitor battery volatge with 240v usage accordinly.

Wes


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## TR5 (Jun 6, 2007)

Just out of interest, if you used an inverter to feed a battery charger, to charge the batteries that the inverter was pulling power from, who would win?

I'm sure I know the answer, but look forward to a more technical analysis of why!


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## spindrifter (Nov 14, 2006)

In the end - neither!

Cheers

David


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## pieterv (Feb 3, 2009)

karlb said:


> pieterv said:
> 
> 
> > CliveMott said:
> ...


You normally cook a much shorter period of time than you heat. And for most people there is much less of a chance of falling asleep when you cook  so you will notice the head ache and can do something about it.

It is the same as having an open gas fire in a bed room. Surely you must have read the stories of people dying because of that.

It is true a short period is not a problem. But when you use it as a main source of heating for a longer period of time, then the oxygen levels will drop and CO will be produced.


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## CliveMott (Mar 10, 2008)

Yes, but in our "good old days" the camper was a converted 1972 Bedford Duple Vista coach and it leaked wind like a sieve. Leisure battery was 350 AH traction batteries. (6 cells). Water heater was a flash boiler that had a pilot flame all the time and went WHOOSH when you turned the hot tap on.

Gas bottle was a big one which we swapped for a full one once a year and used the part used one to supply the house hob.

We never had a space heater. But we never intended camping in the cold!

We just cuddled up if we had to!!!

http://www.motts.org/


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## pieterv (Feb 3, 2009)

If it is that drafty maybe a little bonfire could keep the "cuddlers" warm? :lol:


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