Caravan aircon performance

Subject:Caravan air con.

Mike, you helped me over 2 years ago with our Dometic 8555 fridge, but I wouldn’t presume that you would remember me. We took delivery of a new Jayco 25.78/5 in early Sept. Van is fitted with Dometic Harrier inverter Air con. External air temp is 34. Air temp at air duct is 14. Unit is set at 18. Temp in van won’t drop under 24. Where we travel, outside air often exceeds mid 40’s. We had a Ibis a/c in our previous van (Jayco 21.64/3) and it performed better over all but still struggled occasionally. The new van has an additional 7 + cubic meters of internal space. I am convinced the Dometic unit will not cope. I need some advice. Do we look at a bigger capacity unit? Should we consider a second unit as a back up, if so what size, and can it be fitted? There is some room at the front roof section that may work. Any help would be appreciated. Thank you.

Awnser:

The Harrier in theory/practice is a very powerful RV aircon.
The main issue we see, is if you allow all the furniture in the van to heat up, then the overall temp in the van will not drop until the furniture is cool. So the aircon needs to be on from 9am in the morning. If you have been running the aircon from early in the morning and still struggling to achieve lower temp then the only other solution would be to add additional air cooling (I am assuming the hairier is working to specification – if you measure the air going into the air con and measure it coming back pout we are looking for at least a drop of 12 degrees – from your info i guess it is working correctly).
Most buses we try to convince people to fit 2 aircons  – see the attached picture of Midnight oils tour bus with 4 aircons, this will actually work well.
To give you some comparison your car aircon is 6-9kw of cooling, the harrier is 3.1kw.
Also we can calculate a homes R value (insulation rating) but a caravan/RV, even if insulated well, is very thin, so almost impossible to calculate. More is always better.
My pick would be a Truma aventa – but we have lots of options, even an underbunk aircon if you can lose some storage space.
Regards
mike

 Follow up reply from customer:

Mike, thanks for your reply. I followed your advice and have run the a/c non stop for a few days. This has cooled the van down to a more acceptable temperature. We also activated the small exhaust fan in the ensuite and placed an oscillating floor stand fan in the main body of the van during the hottest part of the day.
Results as follows.
Day time. External air temp 38/40. Internal air temp 24. Unit setting 18. Comfort level with oscillating fan is very acceptable.
Night time. Ext air temp, 24/27. Internal air temp 18/20. Unit setting 18. Oscillating fan not required.
Noise level is far more acceptable than the Ibis in our previous Silverline. No more banging and clunking as unit stops and starts. So far so good. Wife is happy, life is happy. Please feel free to use my comments if you feel they are relevant. Thanks once again. Regards, Philip

Our fridge has stopped working – RM361 3 way fridge

Hi, our fridge has stopped working and I was wondering if you provide a mobile service to come out and check it for us please?
Answer:

no mobile service available – we will need to run the fridge for 4 to 6 hours to get a proper diagnosis on it.

Suggest you remove the fridge and drop it in to us – this is better as we can hook up our own element and run overnight to establish how well the cooling unit is working (or not working).

If you cant remove the fridge – then you will need to call and make an appointment to bring your van to us.

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Leveling legs on “A Class” Motorhome – Titan Redfoot Leveling System

Fitting of Levelling legs to Iveco motorhome.

This motor-home has a slideout with a 3 way fridge mounted into the actual slideout.

We set the Redfoot Leveling legs so the fridge is completely level.

This is one of the benefits of a system like the Titan Redfoot leveling system. The van once leveled does not sway as you move about the van.

We place the control module near the door so it is easy to step out and set the system to auto-level your motorhome.

The main hydraulic pump system is mounted into a lower locker (on this motorhome we choose to place it in a little used locker under the slide-out).

We mounted the legs quite high to ensure plenty of ground clearance will still providing 5 inches of lift.

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Connecting Lithium Batteries to increase capacity

We are seeing a few vans coming in to visit with us and noticing they have multiple lithium batteries joined in parallel. We have always avoided this and insist our customers buy the correct size system. But we often lose the sale to someone else due to them offering a “cheap” large capacity system by joining 2 cheap batteries in parallel.

This article explains very well why we dont offer a inferior way of setting up a lithium system. If you are going to spend good money on a very expensive battery system then it should be done properly.

from http://www.enerdrive.com.au/connecting-epower-b-tec-lithium-battery-series-parallel/

Can I Connect the ePOWER B-TEC Lithium Battery in Series or Parallel

The two questions we have been constantly asked about the ePOWER B-TEC batteries is;

Q1: “Can I connect these in parallel to increase the overall capacity”

Q2: “Can I connect these in series to increase the overall voltage”

A1: When manufactures of lithium cells build batteries, careful consideration is taken to choose matching cells to build the battery pack. The batteries are assembled by the manufacture that is experienced and certified to test and assemble battery packs. The individual cells are tested and sorted by machine so that each ePOWER B-TEC battery pack has matching cells with the same capacity and internal resistance.

Paralleling individual lithium batteries like the ePOWER B-TEC unit is like taking out a lottery ticket. There is a million to one chance that you would end up with two lithium batteries off the shelf at your local retailer with exactly the same capacity & resistance.

When assembling lithium-ion cells into functional battery packs, it is common to connect multiple cells in parallel. When lithium ion battery packs are connected in parallel and cycled, matching of internal resistance is important in ensuring long cycle life of the battery pack. Specifically, a 20% difference in cell internal resistance between two battery packs cycled in parallel can lead to approximately 40% reduction in cycle life when compared to two batteries parallel-connected with the same internal resistance.

 

Internal resistance mismatch becomes an important problem for applications where the lithium battery packs are paralleled and subjected to high C rates, (i.e. large inverter loads and moderate to high charge rates) and are also required to have a long cycle life.

The detrimental effect of internal resistance mismatch between parallel-connected batteries arises because differences in internal resistance lead to uneven current distribution and capacity between the batteries, resulting in a decrease in battery pack life and performance.

The ePOWER B-TEC batteries internal management system (BMS) monitors and optimize each single prismatic cell within the battery during charge & discharge. However the BMS does not have the ability of making a physical connection to a second BMS system for balancing of the cells between each battery.

A2: In series connected batteries, charging and discharging is inherently limited to the condition of the ‘weakest’ cell. This is particularly so with lithium-iron (LiFePO4) batteries.

A weaker cell would cause an imbalance. A weak cell may not fail immediately but will get exhausted more quickly than the strong ones when under load. On charge, the low cell fills up before the strong ones because there is less to fill and it remains in “over-charge” longer than the others. On discharge, the weak cell empties first and gets hammered by the stronger cells. Cells in multi-packs must be matched, especially when used under heavy loads.

Again, the chances of finding two ePOWER B-TEC batteries off the shelf, with exactly the same individual cell capacity in each battery would be near impossible.

So bottom line;

Can I parallel connect the ePOWER B-TEC lithium batteries?

The short answer is yes. BUT as described above, overall performance of the battery pack and life expectancy will be reduced.

Can I series connect the ePOWER B-TEC lithium batteries?

The short answer is no. Early failure of the battery pack is virtually guaranteed due to the mismatch in cell capacities.

PLEASE NOTE: For absolute maximum performance and lifespan, Enerdrive do not warrant the ePOWER B-TEC product in a parallel or series connection configuration.

If you are requiring a larger battery system than the ePOWER B-TEC battery, please look at the Enerdrive Lithium Power Pack Systems which can offer the level of cell/battery balancing protection.

Waeco Reversing Camera

Can you please tell me if the Waeco cameras are PAL or NTSC video?

They are PAL/NTSC (automatic switching).

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Off-road Camper Trailer with Truma Gas Heater

Our customer desired heating in there offroad camper. They wished to only carry gas on board and so we fitted a Truma E2400 Gas Heater.

 

 

 

 

Due to the location of the exhuast and the possiblity of burnt gases coming into the camper – we fitted a safety switch, to keep it safe and complaint.

 

 

 

 

 

 

 

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Ultimate Campers Offroad camper – upgrade

Earlier Ultimate brand campers have a 3-way fridge fitted to them as standard.

Unfortunately it gives disappointing performance due to its location and not being a tropically rate fridge.

These are a clever little camper - with a few upgrades an older one is a great buy.

We recommend changing out the RM2350 3 way fridge with a CRX-110 12 volt compressor fridge.

This means an upgrade to the battery storage. We normally fit 2 x 110amp batteries, a decent size 240volt charger and DC/DC charging system to charge the AGM batteries whilst you are driving.

We also usually add in an Anderson connector so you can utilise your portable solar.

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Ford Transit Van conversion to motorhome

Self conversion for Van to motorhome

Customer is doing a self conversion for Van to motorhome.

We fitted 300watts of solar, Battery charger, DC/DC charging system, 2 x 110amp AGM batteries, LED interior lightCRX-110 Waeco fridge, Roof vent and 240 volt inlet and powerpoints.

Ready for the customer to finish off the build.

 

 

Risks of using a heater in a Caravan or Motorhome.

Diesel heating is considered a very safe method of heating a Caravan or Motorhome.

Below we explain why:

Carbon monoxide poisoning is your main risk of heating in a confined space. Carbon monoxide is a colorless and odorless gas. It forms when a carbon-based substance (coal, LP gas, petrol, diesel etc, hydrocarbon) burns without enough air. The(only minor)indications are: headache, nausea, fatigue, and then unconsciousness. If you sleep, you may never wake up again. Carbon monoxide is rightly called the ‘silent killer’. It also causes brain damage at minor concentrations.

When burning a combustible fuel you are starting primarily with a Hydrocarbon molecule. When you start to burn a Hydrocarbon, Carbon monoxide (CO) is formed, if it carries on burning the CO turns into Carbon Dioxide (CO2). The major way in which combustion can be stopped at that point is through a lack of available oxygen, this also causes unburnt diesel fumes and smoke. Diesels heaters are designed to over supply oxygen (lean burn) under almost all conditions. Thus the CO production is almost nil and any potential smoke is reduced. Having lots of extra air does provide lots of nitrogen and left-over oxygen.

The primary products of diesel fuel combustion are carbon dioxide, nitrogen, heat and water vapour (typically all in the normal air we breathe).

Your second risk is oxygen deprivation. We need about a half a cubic metre of air an hour, of which we convert about 4% into carbon dioxide. If you are in a confined space the exhaled carbon dioxide level rises. As a result, remaining oxygen level falls. It is normally 21%, but symptoms (such as fatigue) set in below 15%. Brain damage consequently occurs shortly after. Oxygen deprivation is serious (or lethal) in poorly ventilated areas.

We use diesel heating in caravans and motor homes specifically to avoid such issues. We draw air from underneath the RV into a tiny furnace, but sealed from the living area. Diesel oil is injected and ignited in this furnace. Air to be heated is blown across the outside of the furnace and ducted to wherever needed. The ‘burnt’ air expels to atmosphere. Burning gas is thus totally sealed from the air heated within the vehicle.

So Diesel heating is considered a very safe method of heating a Caravan or Motorhome. This also explains why there are no requirements for certification of your install. We do recommend you utilise a suitably competent person to carry out your install as we have seen some very poor installations, some even carried out by caravan and motor-home manufacturers.