Mileo 294 shower problem - help

Trinity
Trinity Forum Participant Posts: 2
edited September 2016 in Motorhomes #1

Hi

We bought the Benimar Mileo 294 last year from Marquis Motorhomes.  It has a 4 kw truma combi system.  The shower produces hot water for 2 to 3 minutes only.  Marquis say that is right and that the boost option does not work on the shower.

Can anyone comment on this can any other benimar owners confirm how long their showers last.

Would be grateful for any advice - thank you

 

Comments

  • MichaelT
    MichaelT Forum Participant Posts: 1,874
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    edited September 2016 #2

    as far as I am aware the boost option on the truma system is nothing to do with the shower per say.  It heats the hot water to a higher temperature than normal so when mixed with cold you have hot water for longer.

    Does the kitchen tap still produce hot water once the shower has stopped, if so I would say the mixer valve is faulty on the shower.  If all the hot water has gone i.e. none from any tap and you ahve had it on boost and the boost icon has stopped flashing
    to indicate its up to temperature then the problem is with the Truma water heater.

    Does the boost icon stop flashing at all?

    Are you using just electric, if so try it on gas to see if that makes a difference, if so it may be one of the elements has gone U/S.

  • Trinity
    Trinity Forum Participant Posts: 2
    edited September 2016 #3

    Hi.. Thank you for reply... we have tried using the boost with electric and gas mix setting and the boost indicator stays flashing... all the hot water goes from the sink and shower and you do not hear the boiler heating during using the shower... I would
    have expected the boiler to be heating once the cold water starts going into the boiler but this doesn't happen.Do you know how long you would expect a shower to last when the boost is up to temperature and mixing with cold water?

  • MichaelT
    MichaelT Forum Participant Posts: 1,874
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    edited September 2016 #4

    We would normally get 2 quickish showers or 1.5 longish ones i.e. Mrs T has a long shower and I get a short one Happy  .  Just try it on gas only it as you say should start to reheat once the water is started to be used and using only gas will determine if its the element that is not working.

    As a footnote ours is a Truma 6 so not sure of the difference, others may help there but the principal is the same just the KW difference I think but once water is up to temp its the same.

  • JCB4X4
    JCB4X4 Forum Participant Posts: 466
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    edited September 2016 #5

    From what you have said in your OP  I think you have the ‘Truma  Combi 4e’

     See: https://www.truma.com/uk/en/heating/combi-4-e.php  this has a total water capacity of 10 Litres with an 1800w electric element that takes about 20mins to raise the temperature of the water
    from 15c to 60c. So if you take two showers, one immediately after the other in theory you can have 5 litres at 60c each.  However 60c is far too hot for the human body and cold will need to be mixed with it, thereby giving a quantity greater than the 5 litres
    mentioned above.

    Now in practice as the hot water is being drawn off it is being replaced in the boiler by cold water and some mixing takes place, thereby constantly reducing the temp of the water  available. Even if the element is working from the moment the hot is being
    drawn off, 1800w will be insufficient to keep up. (theoretically only 1 litre per 2mins).

    You say that you only get hot water for 2-3mins.Have you tried measuring the amount of hot supplied at one go as you may actually be drawing off all of the boiler capacity during that time.  Although I have no experience of this particular system, 2-3mins
    does seem a very short time to me.

  • JCB4X4
    JCB4X4 Forum Participant Posts: 466
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    edited September 2016 #6


    If only water is being heated up (during summer operation), a temperature of 60 degrees is reached after around 20 minutes.

    If the living area is being heated and the boiler is being operated (during winter operation), a water temperature of 60 degrees is reached after around 80 minutes.

    It is possible to heat up the water in electrical operation alone (i.e. entirely without gas). The heating time in electrical operation is around 45 minutes.


     

    The above is taken from Q&A's 
    https://www.truma.com/uk/en/heating/combi-4-e.php 

  • young thomas
    young thomas Forum Participant Posts: 11,356
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    edited September 2016 #7

    agree with pretty much all of the above replies...

    like Michael, we get two showers (one straight after the other) from one heated tank of water....heat 10 ltr to 60 deg, mixed with cold gives about 13 ltr of hot enough water...

    i get say 5 ltr, OH will have about 8 ltr...

    aswell as heating the water to a slightly higher temp, the other thing it does is to turn off any heating to focus on the water...

    the only difference in the combi 4 and 6 is the power available on gas (4 or 6 kw) and mixed (3.8 or  5.8 kw) power sources.

    on electric only, either can heat with 900 or 1800 watts.

    either can heat to 40 or 60 deg, the chosen power source will determine the rate of heating.

    while its true to say that hot water is being replenished with cold, the cold comes in at the bottom and the hot goes out at the top, so it doesnt drag the temp down 'too' quickly....

    two showers should be easily doable from one heating....

     

  • JCB4X4
    JCB4X4 Forum Participant Posts: 466
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    edited September 2016 #8

    ..."the only difference in the combi 4 and 6 is the power available on gas (4 or 6 kw) and mixed (3.8 or  5.8 kw) power sources.on electric only, either can heat with 900 or 1800 watts"...

    I am a little puzzeled as to why the Combined  power output is actualy less than that of the Gas alone. Undecided and can you heat the van its-self using Electricity only?

    PS. I seem to be having some trouble getting this to post tonight Frown

     

  • MichaelT
    MichaelT Forum Participant Posts: 1,874
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    edited September 2016 #9

    I am not sure of the logic of the power either I thought on dual fuel it gave the higher output, but yes you can heat the van on electric only but as BB says if you have the water on boost it will prioritise that over heating. On a cold day to warm the van
    faster put it on dual fuel and it will heat faster. 

  • young thomas
    young thomas Forum Participant Posts: 11,356
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    edited September 2016 #10

    when on mixed mode, the full 1800w of the electric side is used (if selected....its possible to have mixed mode with 900w electric...for use on a low amp site?)

    the gas side only uses 2kw (on the combi 4) or 4kw (on the combi 6). dont understand the logic but these are the figures AFAIK.

    i think the ALDE units use full gas and electric outputs to give their 'mixed mode' totals....again AFAIK.

    i have a combi 6E.

    as Michael says, heating the van is perfectly possible on electric only (900/1800w) as is water heating.

    with the latest control panel, its possible to manually control the fan speed....by ramping this up to 'high' even the lowish electric output can be boosted around the van in a far better way than the older system, where the fan speed was determined by heat output.....so, low heat (electric) meant low fan.....which in turn usually meant van not warm enough...

    the change in the fan speed has really made a huge difference.

  • JCB4X4
    JCB4X4 Forum Participant Posts: 466
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    edited September 2016 #11

    Apologies to OP for going a little off topic but, as a non-caravanning relative of mine is about to join the fraternity, I am being asked questions about heating. Surely if the heat output on Gas alone is greater than the Dual output, although the difference is small, the van would heat up quicker on the Gas setting, so do you find this not to be the case?

    BoleroBoy. You say that the 4 E only uses 2kw on gas yet Truma in their Technical Details:  Rated thermal output claim 2000/40000w, yet quote at: Rated thermal output in mixed operation 3800w. All of which is a little confusing.  

    I am wondering if theses appliances have the potential for localised internal over-heating issues, due to their design constraints, when dual output is used. Undecided

  • young thomas
    young thomas Forum Participant Posts: 11,356
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    edited September 2016 #12

    JCB, here goes....

    yes, the difference on gas and mixed is only marginal, however, if you are on an ehu (and you want a fast heat up) mixed mode will do very nicely but only use half the gas....as its also using electric which youll probably have paid for.

    using gas only might be marginally faster (ill wager you wont notice the difference) but makes no use of this paid for leccy.

    perhaps my previous post was a bit confusing....thought i understood it....lol.....

    ok....combi 4e.....

    when on gas only...will output 4kw (hence rated at 4000w)

    when on eletric only, you can select either 900w or 1800w.

    when on mixed mode the gas portion is reduced to only 2kw and to this you have to add the selected electric power....either 900w or 1800w...

    so max mixed output is 2kw + 1800w = 3800w

    if the lower electric value of 900w is selected in mixed mode the max output is 2kw + 900w = 2900w

    hope thats a little clearerHappy

  • JCB4X4
    JCB4X4 Forum Participant Posts: 466
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    edited September 2016 #13

    BoleroBoy

    Thank you!  Your post above makes perfect sense and is in line with the conclusion I was beginning to come to, as this is the only way the figures can be added together to make Truma’s published totals. I am now more convinced, as I said earlier, that these appliances have the potential for localised internal over-heating issues, due to their design constraints, hence the drop 4kw to 2kw output when dual output is used. Does anyone have a more rational explanation as to why the 4kw Gas & 1800w Electricity elements are not used in conjunction so as to give a total output of 5.8kw?

     

  • young thomas
    young thomas Forum Participant Posts: 11,356
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    edited September 2016 #14

    Truma's answer to customers might be....if you need these levels of heat, buy a combi 6Happy

    gas only 6kw

    mixed 4kw + 1800w......= 5.8kw



  • JCB4X4
    JCB4X4 Forum Participant Posts: 466
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    edited September 2016 #15

    That certainly is an answer but if the van of your choice is fitted with the Combi 4 as standard, it would be an expensive one.  However it is good to understand exactly just what the potential output of any heating system is and just how it operates, as
    this will give you a better idea if it will be able to meet your requirements.

  • young thomas
    young thomas Forum Participant Posts: 11,356
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    edited September 2016 #16

    a combi 4 running on 'gas only' or 'mixed mode' whacks out a fair chunk of heat, and with the latest control of the fan (being able to choose 'high') will push that heat around the van to warm most vans sufficiently.

    when on ehu, even running at 1800w, the revised fan speeds really can make this lowish output go a long way.

    we have a 7.35m MH and find that, in most circumstances, the '1800w + high fan speed' selection is plenty....

    although we have a combi 6E, electric power is identical to the 4E.

    JCB, are you having any specific issues with your heating or were you just curious about the 'figures'?Happy

  • JCB4X4
    JCB4X4 Forum Participant Posts: 466
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    edited September 2016 #17

    BoleroBoy,

    I have no issues with my own heating system, it is as I said in an earlier post that …”a non-caravanning relative of mine is about to join the fraternity, I am being asked questions about heating”… and the fact that this topic came up at very much the same time that has caught my interest.

     I have operating experience of separate Warn Air and Water Heating systems and the Alde Wet system but non involving Combi systems in C/vans or MH’s. Once I became involved I just wanted to know all I possibly could. I do like to know and understand just what it is that is going on behind the scenes with such appliances.

    Many thanks again for your input .Happy

    JCB4x4 Cool

  • young thomas
    young thomas Forum Participant Posts: 11,356
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    edited September 2016 #18

    Happy to helpHappy