Aquaroll - Heated?

[Grey13]

Ericmark: An interesting point not often discussed on this forum. Legionella risk.

This thread is specifically regarding increasing showering hot water supply but I wonder how many people take precautions regarding van water systems and legionella risk? I have started a new thread as a matter of interest to see what the general feeling is.

https://www.practicalcaravan.com/forum/technical/56805-legionella-is-it-a-problem-in-caravan-s#456987

 

[otherclive]

Ericmark: An interesting point not often discussed on this forum. Legionella risk.

This thread is specifically regarding increasing showering hot water supply but I wonder how many people take precautions regarding van water systems and legionella risk? I have started a new thread as a matter of interest to see what the general feeling is.

]https://www.practicalcaravan.com/forum/technical/56805-legionella-is-it-a-problem-in-caravan-s#456987

https://www.practicalcaravan.com/fo...la-is-it-a-problem-in-caravan-s#456987[/quote
I sterilise my system twice a year and when arriving on site just fill the system with site water via the aqua roll. We have never suffered tummy bugs and Legionella is most likely to come from the shower head but still extremely low probability in your caravan. Mine is stainless steel and when we use the shower for the first time I tend to run hot water only for less than a couple of minutes otherwise Im into a naked run to refill the aqua roll and reheat a tank of water. I don’t take this to be a specific action regards to legionella more the need to stabilise the temperature. On leaving the site I drain the hot tank and system including the shower hose/head, so theres little left for it to breed in as it requires moisture and a set range of temperature conditions. So I think that the reason the risk isn't discussed on the Forum is that it's one that is extremely unlikely to materialise in the caravan. If anyone should worry about Legionella whilst caravanning I would advise them not to tow a caravan on the public highway, or better still stay in bed.

 

[paws]

I find this a very interesting topic, with many excellent and ingenious suggestions.

I'm afraid I'm not up to making calculations of heat loss/gain, flow rates and the like, but how about this suggestion...

Pour a kettle full of hot water into the nearly full aqua roll.....

adjust the temperature required by initially using less or more hot water ( kettle and saucepan of hot water etc) and then enjoy a long lasting hot shower...
Hope this helps, and of course
Happy Caravanning
paws

That's another way, but from a practical point of view adding 1L of boiling water to 40L at 10C will only raise the water by about 2.5C. so to get it to 30C would need about 8L. - It all seems a bit over the top literally as the full water container would indeed over flow.

From paws:
I did say in my original post " a nearly full Aqua roll"... it's necessary to leave some space for the hot water....

There is no need to heat the water in the aqua roll to 30 degrees there will usually be around 9 litres of piping hot water in the caravan's heater tank (or there is in mine!) this 9 litres of hot is mixed with the cooler water from the aqua roll at the shower to provide the required comfortable level.
The required rise in temperature of the aqua roll water is therefore significantly reduced.....

I have never tried this on my caravan as with the 9 litres of hot water from "tank"/water heater coupled with the 22 litres of cool water from the simple polythene water carrier that we use ( I've never had the need for an aqua roll etc) It gives me a very pleasant shower of adequate duration and then Mrs paws showers whilst I dress, it provides her with a very pleasant and effective shower and still leaves water left over for other purposes before refilling is required.

I do remember from my early boating days using a garden rose sprayer (the pump up kind) with a kettle of water from the Primus topped up with cold, gave a very satisfactory shower, of adequate duration and temperature ( although I do admit that there was considerably less of me to shower, in those days, compared with today!!)

As always Regards to all and Happy Caravanning
paws

 

[Grey13]

UPDATE

As some will know have been slowly making headway with my mission to have a truly cosy longish shower IN MY VAN.

I started out looking at putting a heating element in my insulated AquaRoll which solicited untold some corny comments. I can now proudly announce that after conducting tests on my Aquarol outside in sub zero temperatures it is possible to at least raise the temp of water to above 30 Deg in about 40 minutes. Bearing in mind that I have spent my life in industrial heating. The problem with this is that in truth you need a heating element physically suitable for the AquaRoll that is short enough to be continually submerged using the float mains feed water supply. You also now need some to automate the element controlling it with a temperature controller of sorts and a measuring probe (thermocouple etc) together with all the necessary wiring and plugs. A mission to say the least.

I have concluded it is so much easier to just add a second water heater in series with the Truma gas/elec heater in situ to boost the supply. This heater has it's own built in controller setting up to 80 deg c or so and a suitable drain for emptying during standing periods. Best of all it is not very expensive.

https://www.propexheatsource.co.uk/heaters/10l-water-heater

 

[otherclive]

UPDATE

As some will know have been slowly making headway with my mission to have a truly cosy longish shower IN MY VAN.

I started out looking at putting a heating element in my insulated AquaRoll which solicited untold some corny comments. I can now proudly announce that after conducting tests on my Aquarol outside in sub zero temperatures it is possible to at least raise the temp of water to above 30 Deg in about 40 minutes. Bearing in mind that I have spent my life in industrial heating. The problem with this is that in truth you need a heating element physically suitable for the AquaRoll that is short enough to be continually submerged using the float mains feed water supply. You also now need some to automate the element controlling it with a temperature controller of sorts and a measuring probe (thermocouple etc) together with all the necessary wiring and plugs. A mission to say the least.

I have concluded it is so much easier to just add a second water heater in series with the Truma gas/elec heater in situ to boost the supply. This heater has it's own built in controller setting up to 80 deg c or so and a suitable drain for emptying during standing periods. Best of all it is not very expensive.

]https://www.propexheatsource.co.uk/heaters/10l-water-heater

https://www.propexheatsource.co.uk/heaters/10l-water-heater[/quote
I had Propex caravan heater and water heater in a French import that we had. The importer fitted the Propex kit. Very good, although the cabin heater was powerful but noisy

 

[ProfJohnL]

Hello Grey,

Its a plan, but have you considered the additional weight detracting from payload ? And i also occurs to me that connecting both the Propex and your existing heaters in series, you will need to consider which is up stream of the other, so that if for any reason you are only using one heater, the hot water from one is not pumped into the unused heater becasue it will be severely diluted. For what its worth, and to maximimise flexibility I would put the propex unit up stream of your other heater, so you have the flexibility of using gas when mains is not available.

 

[Buckman]

Hello Grey,

Its a plan, but have you considered the additional weight detracting from payload ? And i also occurs to me that connecting both the Propex and your existing heaters in series, you will need to consider which is up stream of the other, so that if for any reason you are only using one heater, the hot water from one is not pumped into the unused heater becasue it will be severely diluted. For what its worth, and to maximimise flexibility I would put the propex unit up stream of your other heater, so you have the flexibility of using gas when mains is not available.

Maybe easier to fit the ALDE continuous hot water system and never run out of hot water!

 

[ProfJohnL]

Hello Buckman,
From purely a practical point of view, the sort of shower that Grey is trying to achieve needs about 5 to 7L of water per minute at about 38 to 40C.

The smallest ALDE unit :-

https://www.alde.co.uk/itemdetails-4.html
can only provide up to 3.5L/m and it doesn't state at what temperature, so its difficult to know for certain but I suspect it would not actually meet Greys wishes.

The are some real practical issues with trying to provide a touring caravan with an instantaneous water heater suitable for a shower. But to explain would take a long post.

 

[Buckman]

Hello Buckman,
From purely a practical point of view, the sort of shower that Grey is trying to achieve needs about 5 to 7L of water per minute at about 38 to 40C.

The smallest ALDE unit :-

https://www.alde.co.uk/itemdetails-4.html
can only provide up to 3.5L/m and it doesn't state at what temperature, so its difficult to know for certain but I suspect it would not actually meet Greys wishes.

The are some real practical issues with trying to provide a touring caravan with an instantaneous water heater suitable for a shower. But to explain would take a long post.

No need for any long post as simply go to the ALDE website and view the Continuous hot water system.

 

[ProfJohnL]

Hello Buckman and Grey

The Alde Flow unit is not a stand alone water heater, it is a pre heater, much as Grey has been looking for, but it is designed for use with other Alde equipment so it might not integrate with non Alde gear. And I'm not convinced it's as 'continuous' as Grey is looking for.

Grey has been striving to improve the length of time he can shower for, so that equates to needing more hot water than is normally available from standard caravan products. But it is a specific requirement, where he needs enough water available at the shower head at about 40C, a caravan shower is frugal and will use about 3.5 to 4 litres of water per minute.

The amount of power needed to heat the water for a continuous shower depends on flow, the desired water temperature increase needed. We know the flow 3.5l/m we know the temperature needed is about 40C. We don't know the cold water temperature. Let's be generous and assume it's 10C. The temp rise is therefore 30C. That require a heat input of 7.2kW.

If the cold water starts at only 5C then the power needed is 9kW!

The Alde web page does not tell us the capability of the flow device, but knowing what I do about the design of caravan heating appliances and the laws of physics, I seriously doubt the Alde can provide a continuous heating capacity of 7.2kw yet alone 9kW to raise the temp. of enough water for a continuous shower lasting more than 3 minutes which it would need to do when the other appliance has run out of hot water.

 

[Buckman]

Hello Buckman and Grey

The Alde Flow unit is not a stand alone water heater, it is a pre heater, much as Grey has been looking for, but it is designed for use with other Alde equipment so it might not integrate with non Alde gear. And I'm not convinced it's as 'continuous' as Grey is looking for.

Grey has been striving to improve the length of time he can shower for, so that equates to needing more hot water than is normally available from standard caravan products. But it is a specific requirement, where he needs enough water available at the shower head at about 40C, a caravan shower is frugal and will use about 3.5 to 4 litres of water per minute.

The amount of power needed to heat the water for a continuous shower depends on flow, the desired water temperature increase needed. We know the flow 3.5l/m we know the temperature needed is about 40C. We don't know the cold water temperature. Let's be generous and assume it's 10C. The temp rise is therefore 30C. That require a heat input of 7.2kW.

If the cold water starts at only 5C then the power needed is 9kW!

The Alde web page does not tell us the capability of the flow device, but knowing what I do about the design of caravan heating appliances and the laws of physics, I seriously doubt the Alde can provide a continuous heating capacity of 7.2kw yet alone 9kW to raise the temp. of enough water for a continuous shower lasting more than 3 minutes which it would need to do when the other appliance has run out of hot water.

As long as there is a water available you will have hot water. I know someone who has it fitted in the caravan and their son also has it fitted. As much hot water as you need and flow is dependent on pump. I am not sure whether it can be fitted to a caravan without ALDE heating but I suspect it can as it is a stand alone unit. We are seriously thinking of having the unit fitted later in the year when we take the caravan to ALDE for the fluid change.

 

[Danddandy]

I'm happy with the standard Alde setup but how much is the Alde Flow?

 

[Dustydog]

I thought this Alde was a preheater. The main water heater kicks out water at 70 deg C. This mixed with the cold water which I suppose could also be preheated may help. Also the shower head volume can be reduced to a bare minimum to extend the shower period. Thus the useable volume of hot water at 40 ish will be greater than people think as it will be mixed with the cold feed.
Good luck with it Grey. Could be a new market out there
I must say the good old splash and dash has never failed us in decades :cheer:

 

[Buckman]

I'm happy with the standard Alde setup but how much is the Alde Flow?

If ALDE fit the cost is about £800. It is a preheater and in a sense does away with the boiler as the water is heated to the correct temperature prior to entering the boiler. The boiler remains in place as a storage tank so you have unlimited hot water

 

[ProfJohnL]

Well I stand to be corrected, but unless the Flow has has a heat input capability of at least 7.2KW it cant keep a continuous ( i.e unlimited and none stop) flow of shower ready water. Its a physical impossibility within the constraints of a caravan.

 

[Buckman]

Well I stand to be corrected, but unless the Flow has has a heat input capability of at least 7.2KW it cant keep a continuous ( i.e unlimited and none stop) flow of shower ready water. Its a physical impossibility within the constraints of a caravan.

It is my understanding that it works on gas and electric to supply the continuous hot water. Why don't you have a word with them on Monday and then come back and explain it to us plebs in English. LOL!

 

[Dustydog]

I need the Prof’s calculations here.
Assuming the pre heater feeds the main heater with water at 40 and the main heater outputs at 70, assume the smallest minimum flow at the shower head 2/3 litres per minute. Add in the factor the 70 needs cooling with cold water maybe , and just maybe , a tolerable continuous temperature of water may be delivered for quite a few minutes
If this isn’t possible why would anyone spend £800 on a piece of kit that won’t deliver hmy:
Beyond me but I am sure the boffins will have a scientific answer.
Meantime I am trying to persuade Grey to use the on site showers

 

[Grey13]

Dusty:

Meantime I am trying to persuade Grey to use the on site showers

Keep it up, however I'm like a dog with a bone, on a mission.......

 

[Craigyoung]

Dusty:

Meantime I am trying to persuade Grey to use the on site showers

Keep it up, however I'm like a dog with a bone, on a mission.......

Nothing wrong with it on site showers Grey as that is all I use as ive been grilled before about this on here , I will use the caravan shower if I have to though !

 

[otherclive]

Dusty:

Meantime I am trying to persuade Grey to use the on site showers

Keep it up, however I'm like a dog with a bone, on a mission.......

Nothing wrong with it on site showers Grey as that is all I use as ive been grilled before about this on here , I will use the caravan shower if I have to though !

Let Grey do his own thing, when he first joined the Forum he explained his clear preference fora prolonged on board shower. Despite my trying to persuade him that a submariners shower is just as cleansing! But I for one follow his efforts to install a better shower system with interest. Vive la differance as they say .........

 

[ProfJohnL]

Well I stand to be corrected, but unless the Flow has has a heat input capability of at least 7.2KW it cant keep a continuous ( i.e unlimited and none stop) flow of shower ready water. Its a physical impossibility within the constraints of a caravan.

It is my understanding that it works on gas and electric to supply the continuous hot water. Why don't you have a word with them on Monday and then come back and explain it to us plebs in English. LOL!

The information that Alde publish about the FLOW on their web site is far from dreadfully incomplete. It does mention "The Alde Flow is our latest ingenious invention, expanding the heat exchange surface to pre-heat the water entering the Alde 3020 Compact HE boiler. This provides continuous hot water." It goes on to mention "calorifiers" which suggests it uses excess heat from and engine cooling system.

If this is the case then it would not be used in a touring caravan.

 

[Buckman]

Well I stand to be corrected, but unless the Flow has has a heat input capability of at least 7.2KW it cant keep a continuous ( i.e unlimited and none stop) flow of shower ready water. Its a physical impossibility within the constraints of a caravan.

It is my understanding that it works on gas and electric to supply the continuous hot water. Why don't you have a word with them on Monday and then come back and explain it to us plebs in English. LOL!

The information that Alde publish about the FLOW on their web site is far from dreadfully incomplete. It does mention "The Alde Flow is our latest ingenious invention, expanding the heat exchange surface to pre-heat the water entering the Alde 3020 Compact HE boiler. This provides continuous hot water." It goes on to mention "calorifiers" which suggests it uses excess heat from and engine cooling system.

If this is the case then it would not be used in a touring caravan.

As you are the wise one is it possible for you to email them and ask the relevant questions as probably most of us are not that clued up on calorific rates etc. and will not know what sort of question to ask. BTW did you read the manual for it? Ta.

Manual

 

[otherclive]

Well I stand to be corrected, but unless the Flow has has a heat input capability of at least 7.2KW it cant keep a continuous ( i.e unlimited and none stop) flow of shower ready water. Its a physical impossibility within the constraints of a caravan.

It is my understanding that it works on gas and electric to supply the continuous hot water. Why don't you have a word with them on Monday and then come back and explain it to us plebs in English. LOL!

The information that Alde publish about the FLOW on their web site is far from dreadfully incomplete. It does mention "The Alde Flow is our latest ingenious invention, expanding the heat exchange surface to pre-heat the water entering the Alde 3020 Compact HE boiler. This provides continuous hot water." It goes on to mention "calorifiers" which suggests it uses excess heat from and engine cooling system.

If this is the case then it would not be used in a touring caravan.

As you are the wise one is it possible for you to email them and ask the relevant questions as probably most of us are not that clued up on calorific rates etc. and will not know what sort of question to ask. BTW did you read the manual for it? Ta.

Manual

From what I’ve read on Greys posts and what he’s done to his caravan I’d be very surprised if he couldnt fathom this one out himself by contacting Alde.

 

[Dustydog]

Well I stand to be corrected, but unless the Flow has has a heat input capability of at least 7.2KW it cant keep a continuous ( i.e unlimited and none stop) flow of shower ready water. Its a physical impossibility within the constraints of a caravan.

It is my understanding that it works on gas and electric to supply the continuous hot water. Why don't you have a word with them on Monday and then come back and explain it to us plebs in English. LOL!

The information that Alde publish about the FLOW on their web site is far from dreadfully incomplete. It does mention "The Alde Flow is our latest ingenious invention, expanding the heat exchange surface to pre-heat the water entering the Alde 3020 Compact HE boiler. This provides continuous hot water." It goes on to mention "calorifiers" which suggests it uses excess heat from and engine cooling system.

If this is the case then it would not be used in a touring caravan.

I’m lost? Surely the water system with the Alde preheater will only be used whilst stationary. No engine running? Are we talking about the same system please?

 

[Buckman]

I’m lost? Surely the water system with the Alde preheater will only be used whilst stationary. No engine running? Are we talking about the same system please?

The system is definitely fitted into caravans as I know of two people who have it fitted and both of them say it is fantastic as always have hot water. I think it can be fitted into any unit that has an ALDE system fitted. However the only way to confirm this is to phone or email ALDE and ask them. We are seriously thinking of fitting the unit into our caravan at the end of the year based on reports from other people who are using the system.