How would you interpret the following;

[Surfer]

Although a Lunar related issue, this is a general question on wording in a book. This is from the 2011 Lunar owner's handbook Page 50

Int/Ext switch When in the internal position the internal pump fitted in the underfloor water tanks is operational. If the water level falls to a pre-determined level it will automatically switch to the external pump until the underfloor water tank level rises.
When in the external position the external pump will be operational and will automatically fill the underfloor water tank. LEDS are situated adjacent to the switch indicating which pump is activated.

The above indicates to me if the water level in the underfloor tank drops to below the pre-determined level, the external pump will top up the underfloor tank to the predetermined level. Dealer is stating that you have to manually switch the pump to external pump for this to happen. We disagree.

The above is one of our issues. The other is when for example you are on external pump and the barrel runs out of water and you switch to the internal supply. Although you switch to internal, the external pump continues to run. Lunar via their design team, electrician etc state that when you switch from the ext pump to internal and the internal tank is full, the external pump should switch off. I have several emails from Lunar that indicate this, but dealer states Lunar is wrong.

We are caught in a Catch 22 situation. With regards to the 1st issue, how do you interpret what the owner's manual states?

 

[NigelHutson]

Surfer,
On my first reading I would agree with you and Lunar, not the Dealer. As you have the handbook, do I take it that you have the caravan to go with it? If so, can you try out the theory?

 

[Damian]

Lunar build the vans and "should" know what should happen.
Dealers sell vans and in a lot of cases do not know how much works, or how things "should" work

 

[Surfer]

We have tried the theory and if the external pump is on and you run out of water and switch to the internal tank the external pump continues to run although water is now flowing from the taps again from the internal tank.

 

[hortimech]

I take it (from looking at the link you supplied) that you have a delta model, this appears to have a levelling device fitted to the internal water tank, this is connected to the control panel. This is where I think your problem lies. My reading of what should happen is: With the switch in the internal position, power is supplied only to the pump inside the internal tank and when you open a tap this is the pump that runs. When the level in the tank drops to a preset limit, the external pump should start and top up the tank and then shut off, all controlled by the levelling device and control panel. If the external pump runs all the time with the switch in the internal position with a full tank, the tank will fill to maximum and then excess water will exit out of the fitted overflow pipe. My reading of this is, that there is either a fault in the levelling device in the tank or the control panel, or there is a wiring fault supplying power to the external pump circuit, which should be isolated with the switch in the internal position. Please note that this is just my reading of the situation and I could be wrong

 

[xtrailman]

For a system to work as described , you would require a low level cut off for the external water barrel, or the onboard pump will run continuously on a empty barrel, assuming a demand for top up water to the internal tank.

And ideally the internal tank should have at lest two level switches for effective water level control, using just one will lead to constant hunting of the top up pump.
I would prefer a manual top up system.

Anyway i thought these systems only used a single pump, but selected the water source usually via solenoid valves or manual changeover valves?

 

[Dustydog]

Int/Ext switch When in the internal position the internal pump fitted in the underfloor water tanks is operational. If the water level falls to a pre-determined level it will automatically switch to the external pump until the underfloor water tank level rises.
When in the external position the external pump will be operational and will automatically fill the underfloor water tank. LEDS are situated adjacent to the switch indicating which pump is activated.

I think I'd ring Lunar Surfer. It's ambiguous.
Looking at my more antiquated system in the Wyoming there are times when I will only want water from the internal tank, not the external. eg on very cold sub zero temperature days. So I will not want the external pump kicking in. Reading the description literally it seems to me whichever position the switch is in the external pump will still try and pump water to the inboard tanks. That can't be right or have I got my whiskers twisted

 

[Surfer]

Each of you are correct with your interpretation which is why people make mistakes due to a manual being ambigious and written in poor English making assumptiosn that every one understands what the engineer is saying. LOL!
The representative for the dealer came out to the caravan today and we ran a few tests. The issue with the external pump running after it has been switched to the internal tank is now resolved, but no one knows why.
However regarding the topping up, what happens is that when the internal tank drops below a certain pre-determined level, i.e. less than 10 litres the external pump will automatically top the internal tank to the 10L mark. It will not fill up the tank. This allows you to continue to use water even though the internal tank is almost empty. In order top up the internal tank to full, you switch it to the external pump and once the internal tank is full, the external pump shuts off.

 

[mistralse]

I have got a headache now.

 

[colin-yorkshire1]

Each of you are correct with your interpretation which is why people make mistakes due to a manual being ambigious and written in poor English making assumptiosn that every one understands what the engineer is saying. LOL!
The representative for the dealer came out to the caravan today and we ran a few tests. The issue with the external pump running after it has been switched to the internal tank is now resolved, but no one knows why.
However regarding the topping up, what happens is that when the internal tank drops below a certain pre-determined level, i.e. less than 10 litres the external pump will automatically top the internal tank to the 10L mark. It will not fill up the tank. This allows you to continue to use water even though the internal tank is almost empty. In order top up the internal tank to full, you switch it to the external pump and once the internal tank is full, the external pump shuts off.

hi Surfer, after picking up this thread this morning I read the instructions on the link and yes it was a bit abiguious, however after trawling through a few hundred pages on the internet regarding related items on self filling systems it seems quite obvious that the internal tank is deemed the main supply and the external carrier (the backup) is there to insure the internal tank doesnot run empty via a series of floats and valve/switches as a means to keep the internal supply at a usable level.
the instance and explaination you describe in your last post supports this. glad you got it sorted.
ps. the system should also support the use of a suitable mains supply instead of the external tank to keep the internal one full like when on a service pitch.
colin

 

[Dustydog]

Hi Colin, Sir Chunky,
If ever a manual was ambiguous this is it. Whichever position the switch is in the external pump at some point will kick in. What if Surfer doesn't want to use his external source overnight say? Surely there must be a way of manually isolating the external pump?

 

[Surfer]

An issue arises when you want to use the onboard tank to empty it and without it filling up again. It is not very pleasant for the person using the pitch afterwards to find 40L of water dumped on it. The only way run it is to let the external barrel run empty and then switch to the onboard. When that starts to run empty the ext pump switches on to try and top it up. You then switch off the pump and drain the remaining 3 - 5 litres in the onboard onto the ground. I am not sure at what level the tank tops up again when low but have been told it is only a few litres.

 

[colin-yorkshire1]

hi King DD,
"Whichever position the switch is in the external pump at some point will kick in" Correct. The external pump it there to fill the internal tank so it does not run short of water.
there will be 2 water levels set inside the (main) internal tank typically 10 and 20 litres, 20 being full and 10 the minimum.
when first setting up, the the internal tank (assuming it is empty after towing) will have to be filled from the external water supply (outside tank or mains supply) using the external position of the switch. once the internal tank is full to 20litres the switch is moved to the internal position so water can be drawn from the the inside tank. at this point the external supply (waterhog) would need filling again,
you now have two full water tanks, the water drawn after this will only come from the inside tank untill the level drops to 10litres at which time the external pump kicks in to keep the water level at 10litres. (much the same way a normal ultrastore heater does) as water is drawn from the internal tank the external pump keeps the water level at 10litres.
"What if Surfer doesn't want to use his external source overnight say? Surely there must be a way of manually isolating the external pump?" this is achieved by switching the external supply on via the switch and filling the internal tank to it's 20liter max, returning the switch back to the internal position means the external pump will not run again untill the level in the internal tank drops to 10 litres.
under normal operating circumstances the switch will be in the internal position only with the water level at 10 litres (exept when the internal tank is required to be filled to 20 litres) then the outside pump can be manually over ridden "via the switch"to fill the internal tank to 20 litres.
I think it is called progress? reading the information I gleened it seems these systems were designed so when using service pitches a constant supply of fresh water is on tap without the need to fill containers. HOWEVER, if a supply is not available there has to be a way to fill the internal tank by other means ie a seperate outside tank. and this is where the the switch and external pump come in.
hope this makes thing clearer .
sir chunky

 

[colin-yorkshire1]

hi Surfer,
yes thats about the size of it however unless there is an unexpected decampment one would know roughly how much water was left in the internal tank once the the external barrel was MT if the pump was disconnected from the van the external pump could not run so the remaining water could be used untill the inside tank was empty via taps or drain,
if you think about it though it is no worse than normal when there is 10liters of hot water and a 40 liter waterhog to gid rid of the water left in the tank can be drained off into the waste hog to wash it out in the same way one does with the hot water.

 

[Surfer]

hi Surfer,
yes thats about the size of it however unless there is an unexpected decampment one would know roughly how much water was left in the internal tank once the the external barrel was MT if the pump was disconnected from the van the external pump could not run so the remaining water could be used untill the inside tank was empty via taps or drain,
if you think about it though it is no worse than normal when there is 10liters of hot water and a 40 liter waterhog to gid rid of the water left in the tank can be drained off into the waste hog to wash it out in the same way one does with the hot water.

Easier to roll an Aquaroll than to lift and pull a waste master or hog. At least with an Aquaroll you could roll it to an area out of the way to dump the water. We hate dumping or wasting water having been brought up in a country where droughts are common and water is more precious than gold.

 

[colin-yorkshire1]

hi Surfer,
yes thats about the size of it however unless there is an unexpected decampment one would know roughly how much water was left in the internal tank once the the external barrel was MT if the pump was disconnected from the van the external pump could not run so the remaining water could be used untill the inside tank was empty via taps or drain,
if you think about it though it is no worse than normal when there is 10liters of hot water and a 40 liter waterhog to gid rid of the water left in the tank can be drained off into the waste hog to wash it out in the same way one does with the hot water.

Easier to roll an Aquaroll than to lift and pull a waste master or hog. At least with an Aquaroll you could roll it to an area out of the way to dump the water. We hate dumping or wasting water having been brought up in a country where droughts are common and water is more precious than gold.

hi, just a suggestion I allways wash out the wastehog with the left over hot water out of the heater, unless one is going to leave it onboard or bottle it theres little one else can do.