Caravan pressure switch water system.

Caravan pressure switch water system.

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Discussion

cpas

Original Poster:

1,661 posts

241 months

Sunday 4th August 2013
quotequote all
Good evening all.

My caravan's water system detects pressure loss when a tap is opened which starts the pump, and turns it off when the tap is closed and the pressure is built up again. However, if the water container is empty, the pump will continuously run until manually switched off, potentially damaging the pump.

Does anyone have any ideas how I can detect when my water barrels are empty and possibly cut the pump off, as the kids seem to be unable to check if the container's empty and if the water runs out then forget to switch the system off or tell me?!!

I was thinking of a warning buzzer when the pump light's on, some sort of pressure mat under the Aquaroll or even a float in the container. Is anything like this available on the market?

littlebasher

3,782 posts

172 months

Sunday 4th August 2013
quotequote all
Internal or external pump? My internal one has run (unintentionally) for ages (more than once) and never caused it an issue

Otherwise

http://aquabuddi.moonfruit.com/

Kenty

5,052 posts

176 months

Dog Star

16,157 posts

169 months

Monday 5th August 2013
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This used to happen with my parents old van, Carver Crystal system iirc. They went through about 3 pumps and they weren't cheap.

(As you can tell we never actually did anything about it, hence the three pumps...)

cpas

Original Poster:

1,661 posts

241 months

Monday 5th August 2013
quotequote all
It's an external, in the Aquaroll, pump. I might delve into these further. Thanks for the replies.

Tyre Smoke

23,018 posts

262 months

Monday 5th August 2013
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No easy or cheap answer, other than turning the pump off at the switch each time? PITA though. Has your van got an on board tank as well? Is it possible to set the fill to go from Aquaroll to internal to tap rather than direct to the tap? At least this gives you a bit of warning/breathing space to fill the Aquaroll.

santona1937

736 posts

131 months

Tuesday 6th August 2013
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what you need is a guage that tells you the state of your tanks, they make them foe the yacht market, called tank tender, they will monitor up to 10 different tanks
hope this helps

cpas

Original Poster:

1,661 posts

241 months

Tuesday 6th August 2013
quotequote all
There aren't any internal tanks, just a couple of external Aquarolls. I did think about linking the two together to even the water usage. I normally turn the switch off but other members of the family normally forget smile

Vladimir

6,917 posts

159 months

Tuesday 6th August 2013
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Our VW California has gauges for both fresh and grey water tanks. Sadly they aren't the most accurate bit better than nothing.

Must be similar available elsewhere?!

rix

2,788 posts

191 months

Tuesday 6th August 2013
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i would guess when its not pulling water the load on the system must decrease. I'm no engineer but could you wire something that detects a certain current range and sounds an alarm?

cpas

Original Poster:

1,661 posts

241 months

Wednesday 7th August 2013
quotequote all
rix said:
i would guess when its not pulling water the load on the system must decrease. I'm no engineer but could you wire something that detects a certain current range and sounds an alarm?
Sounds like a plan. The trouble is though that the current probably varies with battery voltage (when it drops aver the weekend) and flow rate depending on how fully taps are opened. I am considering a circuit that sounds a buzzer if the pump remains on for more than a few seconds (as there is a red 'running' LED on the control panel I could tap off).

rix

2,788 posts

191 months

Thursday 8th August 2013
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cpas said:
Sounds like a plan. The trouble is though that the current probably varies with battery voltage (when it drops aver the weekend) and flow rate depending on how fully taps are opened. I am considering a circuit that sounds a buzzer if the pump remains on for more than a few seconds (as there is a red 'running' LED on the control panel I could tap off).
Sounds like a good plan, but it will need to be switchable unless you never use the shower, lol

cpas

Original Poster:

1,661 posts

241 months

Saturday 10th August 2013
quotequote all
rix said:
cpas said:
Sounds like a plan. The trouble is though that the current probably varies with battery voltage (when it drops aver the weekend) and flow rate depending on how fully taps are opened. I am considering a circuit that sounds a buzzer if the pump remains on for more than a few seconds (as there is a red 'running' LED on the control panel I could tap off).
Sounds like a good plan, but it will need to be switchable unless you never use the shower, lol
If I was in the shower, the buzzer would be in the main room so annoying everybody else apart from me - LOL.

apgh

2 posts

127 months

Thursday 31st October 2013
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cpas

I am working on a project with a friend which does exactly what you want plus lots more. I also have a pressure switch based water system and even burnt out a submersible pump because of an empty barrel, so decided to use my limited skills to design a solution. This project stepped up a gear when my acquaintance who is an expert in electronics and software, joined me and moved the design up to a whole new level. I stress this is not a commercial available device, just something we are working on.

Our system which is still being tested by me has the following features :-
1/ Designed for caravans with onboard tank and either external barrel pump or mains water tap as found on a deluxe pitch.
2/ If either Tank or Barrel runs out of water the system shuts down and gives warning beeps.
3/ Automatically fills the Tank when system turned on when you arrive at a site after connecting a submersible pump (if you forget the pump or put it in an empty barrel it just runs for approximately 2 seconds before turn pump off, then it beeps at you).
4/ Automatically re-fills the tank when level drops below a height set by user.
5/ Tells you the amount of water in the tank as a percentage.
6/ You can select with the touch of a button where the water comes from, either Automatic / Internal / External / Mains water Tap.
7/ If required you can pre-heat the water in Tank to a set temperature when on mains electric which means you should never run out of hot water in the winter (unless you use more than the tank holds, 35 litres in my case). In my case this pre-heat happens at night and is virtually silent.
8/ Best of all you can control everything using an iPhone, Android mobile or tablet which displays the water levels and other information..

I must state again this is not available, although I would like to think it could be one day.


Regards a dedicated UK winter caravanner, that dabbles in electronics.

cpas

Original Poster:

1,661 posts

241 months

Monday 4th November 2013
quotequote all
apgh said:
cpas

I am working on a project with a friend which does exactly what you want plus lots more. I also have a pressure switch based water system and even burnt out a submersible pump because of an empty barrel, so decided to use my limited skills to design a solution. This project stepped up a gear when my acquaintance who is an expert in electronics and software, joined me and moved the design up to a whole new level. I stress this is not a commercial available device, just something we are working on.

Our system which is still being tested by me has the following features :-
1/ Designed for caravans with onboard tank and either external barrel pump or mains water tap as found on a deluxe pitch.
2/ If either Tank or Barrel runs out of water the system shuts down and gives warning beeps.
3/ Automatically fills the Tank when system turned on when you arrive at a site after connecting a submersible pump (if you forget the pump or put it in an empty barrel it just runs for approximately 2 seconds before turn pump off, then it beeps at you).
4/ Automatically re-fills the tank when level drops below a height set by user.
5/ Tells you the amount of water in the tank as a percentage.
6/ You can select with the touch of a button where the water comes from, either Automatic / Internal / External / Mains water Tap.
7/ If required you can pre-heat the water in Tank to a set temperature when on mains electric which means you should never run out of hot water in the winter (unless you use more than the tank holds, 35 litres in my case). In my case this pre-heat happens at night and is virtually silent.
8/ Best of all you can control everything using an iPhone, Android mobile or tablet which displays the water levels and other information..

I must state again this is not available, although I would like to think it could be one day.


Regards a dedicated UK winter caravanner, that dabbles in electronics.
I like the 'software' approach - it would put any muckled-up electronics version I could do to shame!! If successful, it could be incorporated into new vans. Would you do a simpler version as well which is easily retro-fitted without too much playing about with wiring? Good luck and I hope it works out.

apgh

2 posts

127 months

Tuesday 3rd December 2013
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cpas said:
I like the 'software' approach - it would put any muckled-up electronics version I could do to shame!! If successful, it could be incorporated into new vans. Would you do a simpler version as well which is easily retro-fitted without too much playing about with wiring? Good luck and I hope it works out.
Hi cpas

Actually a simple version that matches your requirements is where I started some years ago but like many engineers, we always want to do more. It had about 6 wires to connect, 2 of which were for a buzzer and when the submersible pump detected absence of water, turned the pump off with a few beeps. These beeps were repeated every minute to remind you to exchange / refill the barrel. It also counted the number of times you turned the tap on and off so when several had occurred, it would try and refill the tank again.

We would like to produce versions for caravan manufacturers and DIY installations but need to overcome problems of interference caused by the many appliances found in modern caravans. From microwave ovens to spark igniters in fridges and fans to pumps in the toilet. If we ever get nearer a finished product I will let you know but don’t hold your breath as they say.

APH

S0 What

3,358 posts

173 months

Tuesday 3rd December 2013
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I once left my in tank pump ruuning overnight and that killed the battery before it killed the pump lol i simply added a fluid level float/switch from a windscreen washer bottle, it set off a buzzer relay that used to be for a lights left on warning system from some ford (i used to break escorts, cortinas and sierras for a decade or so), the float in question simply bolted up through the tank in the same way a cold water tank float seals with 2 sealing washers inside and out, i used extra sealant (tiger seal as i had some left over from another sticking on project), i probably could have used a relay to cut the power to the pump but used what i had to hand.



Edited by S0 What on Tuesday 3rd December 18:09

cpas

Original Poster:

1,661 posts

241 months

Tuesday 3rd December 2013
quotequote all
I did think about a float but as my water containers are external Aquarolls, I though rolling them along the ground would soon destroy the float mechanism. I suppose a capacitance or contact pad/switch could work as it would be solid state.

maffski

1,868 posts

160 months

Wednesday 4th December 2013
quotequote all
cpas said:
I did think about a float but as my water containers are external Aquarolls, I though rolling them along the ground would soon destroy the float mechanism. I suppose a capacitance or contact pad/switch could work as it would be solid state.
How about some kind of flow meter in the pipework?