Underfloor Heating

[RonB]

I would like to enlist the help and knowledge of fellow forum members to convince myself, and others, that although slightly ancient I am still sound of mind. I would therefore be most grateful for your answer to the following question - What is your understanding of the description '230v Underfloor Heating' when used to describe a motorhome with a double floor construction enclosing water tanks and other service items? This is not a trick question and the answer may be obvious. However, your answer is important to me, and all motorhome owners come to that, and I would really appreciate as many replies as possible. Please don't get bogged down with lots of alternative suggestions as these could get numerous, I only require the one that is standard to motorhome use. All will be revealed when I am able to comment. Have fun, and thanks in anticipation of your replies. Ron

[docted]

Ron This will relate to a heating system by Alde which uses a network of radiators to heat your van in a similar fashion to central heating at home. Water is heated and pumped through the radiators. It can also be fuelled by gas. It is a very efffective method of heating although you do not have a blown air sytem for use during the summer. Docted

[Derek Uzzell]

The only system I'm aware of that meets your description involves the "heated floor" concept that (I think) is unique to Hymer S7 and S8 designs. Not sure who makes it - Truma presumably.

[Derek Uzzell]

RonB: While I was mowing the lawn I mulled over your question. (See ladies, some men can multi-task!) and I confess that I don't really know what you are on about. You asked "What is your understanding of the description '230v Underfloor Heating' when used to describe a motorhome with a double floor construction enclosing water tanks and other service items?" I've never heard "230v Underfloor Heating" employed as a standard phrase relating to motorhomes with between-floor tanks/services. The Hymer system I mentioned comprises, in the lounge and cab areas, a genuine heated floor through which run hot-water carrying pipes that extend beneath the mattress of the fixed rear bed and that feed convector heaters behind the cab seats. I understand that the 'boiler' component has 230V or gas heating capability. This system is supplemented by a Truma C6002 gas blown-air/water heater, plus (for cab/windscreen heating) a Truma E2400 gas blown-air appliance. The Alde Compact 3000 system referred to by docted heats air by convection. Water heated by gas or 230V (or exploiting the vehicle's engine coolant) is pumped through narrow diameter pipes feeding convector radiators. As docted says - just like ordinary domestic 'wet' central heating. Where a motorhome has double-floor construction, it's probable that some of the pipes will travel between the floors, or even that a radiator might be embedded within the floors, but it needs emphasising that the Compact 3000 can provide an output of 6kW on gas, but only 2kW (or optionally 3kW) on 230V. What I'm getting at is that the Alde system is predominately gas rather than 230V and that the heat it provides is primarily above-floor, with any underfloor heating as an incidental by-product. This appears to leave just Truma's C6002EH appliance in the frame. With a double-floor motorhome design the Truma 'Combi' air/water heater is usually mounted on the lower floor and, because it makes perfect sense, the blown-air ducting is then routed between the floors. As a result, anything (tanks, batteries, etc.) within the between-floor cavity that's within range of the heat coming off the blown-air ducts will also be warmed up. However, until the recent arrival of the C6002EH, Combi heaters had a gas-only blown-air capability. Although C6002EH offers mains-electricity air-heating, it's only 900W or 1800W output and its effectiveness in performing a '230v Underfloor Heating' role is debatable even if the system were in constant use. Certainly (as with the Alde system) I'd consider the capability a by-product of the air-heating rather than deliberately designed underfloor heating. Over to you Ron - I've done my best and if you want a more focused answer I believe you'll need to ask a less open-ended question.

[RonB]

Thank you for your replies so far gentlemen. Anymore opinions please? Don't forget I'm only asking for the normal way in which you would heat underfloor areas by 230v means. Have fun Ron

[colin]

My opinion is; I look forward to when you are able to comment and how as a T25 owner it will be important to me as you originaly stated

[bertieburstner]

We have a Burstner Elegance motorhome (double bottom) and had as an option a factory fitted underfloor heating system for I think about £150 extra. Basically there is an on off switch by the door. Where anything else is heaven knows! When you are hooked up to mains it "heats" the floor, I assume by some system of thin wires. There is no thermostat, it's either on or off. It doesn't provide enough heat to dispense with other forms of heating, but it's nice in the middle of night going to the loo!. No idea who makes it, but it apparently could only be factory fitted at time of construction. Hope this is useful.

[Derek Uzzell]

How intriguing - I've never heard of that before. I've looked at the 2006 Burstner brochure and the option you mention is referred to as "Electric underfloor heating 230V". It's priced at £206 and adds 2kg to the vehicle's weight. As it seems to be available for all current Burstner motorhomes (irrespective of design or base-vehicle) I'd go along with your assumption that the heating comes from wires embedded in the floor itself.

[RonB]

You've ruined my day Bertie, I was hoping that nobody would have heard of it, like Derek and I for a start. However, I would hardly call this system standard to motorhome use. My situation is this. When ordering a new motorhome I specified that it must have electric underfloor space heating to prevent the water tanks,etc, freezing up. We had this facility on our last van, a Burstner 747, so I was well aware of its value during continental winters when one is trying to conserve gas. I also asked that my request be shown on the order form and it was, in the form '230v underfloor heating', which I took at face value to mean what I had described. What I have however, is this Burstner 'foot warming' system that is totally useless to our needs. I am told that probably an electric sheet element is sandwiched between the top floor and its vinyl floor covering. Wherever it is, it provides no heat whatsoever to the underfloor area. I'm sorry that I couldn't be more spacific in putting the question as I didn't want to be seen leading toward the answer. My own answer, for a standard set-up, would have been that it meant 'a form of electric heating between the floors of the vehicle, normally blown air or radiated' - or anything else come to that, so long as it heated that particular area. As my dealer will not even reply to my, courteous so far, complaints on the subject it looks like I will have to get legal. However, if lessons are learned then it could benefit us all, or am I being naive? Incidentally Derek, our previous system was an Alde 3000 which did include radiators to the underfloor and was a beauty. In fact the garage was the hottest part of the van and a bit of a waste really! Relevant to the subject, I now have this picture of you cutting your lawn with a pair of scissors that had been sold to you as a mower (Mow - to cut down). Well, yes it does mow, but not the way wanted. See my point? Have fun. Ron

[olley]

Hi you can buy electric heating panels that you can tile on top of, they are very thin plastic sheets with wires embedded in them, they aren't very powerful, around 150-200watts per square metre, just warm the tiles really, maybe thats what you have. See here: http://www.floorheating.ltd.uk/products.php?CAT_ID=6 Olley

[Mel B]

Hi Ron The dreaded 'dealers' strike again, no one should ever assume anything when it comes to purchasing a motorhome from a dealers, even the most reputable ones can make mistakes, good dealers will, however, try to rectify the problem, however, as you've found out to your cost, some won't. [QUOTE]RonB - 2006-05-16 10:13 PM ... I specified that it must have [b]electric underfloor space heating[/b] ... on the order form ... it was, in the form [b]'230v underfloor heating',[/b] [/QUOTE] spot the missing word ... if you see what I mean! [b]Space[/b], the final frontier and all that ... in this case it has made a massive difference. It is down to interpretation and unless it was specifically described on the order sheet as 'space' heating I doubt, unfortunately, if you will get anywhere with the dealers as it is going to be very difficult to prove that you meant space heating and that this is what you stipulated to them. Not good I know but if they can riddle out of it they will. As for the legal route, I'm sorry to say that I think it will be a total waste of time and effort as you cannot prove anything - it will be your word against theirs and I know from experience that this is not a winning scenario. Unfortunate but true. Best bet, I would suggest, is to try to seek out some form of post production system that can be fitted and linked to your van's existing electrics or 'normal' heating system. Good luck.

[Guest peter]

It's probably a system of self regulating cable heater. It's 2 parallel wires as long as you wish. They are not terminated at the other end to form a circuit. The circuit is formed through the semiconducting Polymer in which the wires are embedded which when cold conducts and generates heat, as it warms up it the resistance gradually decreases and heat build up also decreases. So it is self regulating. I was involved in manufacturing this system of heating cable years ago and we sold it to British Rail for attaching to the Points to stop them freezing in winter. But it was hellish expensive in those days in order to recover developement costs.

[rupert123]

[QUOTE]RonB - 2006-05-13 8:40 PM Thank you for your replies so far gentlemen. Anymore opinions please? Don't forget I'm only asking for the normal way in which you would heat underfloor areas by 230v means. Have fun Ron[/QUOTE] In a double skin floor easy. Remove top floor fix heater wires in place, fill void with concrete, replace top floor and carpets, plug in. Job Done

[Guest JudgeMental]

[QUOTE]RonB - 2006-05-13 8:40 PM Thank you for your replies so far gentlemen. Anymore opinions please? Don't forget I'm only asking for the normal way in which you would heat underfloor areas by 230v means. Have fun Ron[/QUOTE] So this is a hypothetical question? would of been helpful if you had said this from the start or given more information. I do not know of a mains only 230v underfloor system. probably because it would be impractical in a motorhome. I have had both the Alde wet water heating 3000 system with underfloor heating in my last van, And currently have C6002EH in a van with double floor... it blows hot air around the underfloor void giving a warm floor underfoot. Its very nice particularly in the bathroom. both systems work on gas and 230v, the Alde is a superior system IMO.

[Derek Uzzell]

I guess this has been risen from the dead as a result of me referring to it on Brian Peters' October 1 2008 "Underfloor heating" threads. See: http://www.outandaboutlive.co.uk/forums/forums/thread-view.asp?tid=13287&posts=4 As RonB's last posting (prior to this thread's resurrection) was more than 2 years ago in May 2006, I'm unclear what value there is in offering him further advice. In fact, I'm a mite doubtful that Ron is still an active forum participant. If he is, hopefully he may be able to comment on Brian's present heating problem.