Whale water heater / pump

[GrinningGrandad]

Having collected our first caravan yesterday we have spent most of the day poring over the manuals and gaining an understanding of how everything works. There is one thing that I am struggling to understand though which is probably more down to my own stupidity than lack of clarity in the instructions.
We have the whale water heating system and whale water master pump. The pump goes into the aqua roll and it’s at this point I get confused!
There is a tank that heats up the hot water. When I switch on the pump does this pump cold water direct to the cold taps? Does it also fill up the hot water tank at the same time? How does hot water get pumped from the hot water tank to the hot taps (considering the pump is in the aqua roll) and What keeps the hot water tank topped up?
Please forgive me if I’m missing something obvious, I’m suffering from information overload at the moment.

 

[Hutch]

GG, welcome to the Forum, the make and model of caravan will help, will help folk on here to help you.
The pump in the Aqua roll will supply water to the water heater but you have to open the taps first to avoid an air blockage, thats hot and cold taps, there will be a switch for the water pump somewhere, to select the pump on or off. The pump in the Aqua roll might need "jiggling" about to prime it , the taps when opened will either by micro switches or pressure sensors give a signal to the 12 volt system to make the pump operate to give you hot and cold water in the caravan.
I hope this helps you.

 

[Anseo]

Welcome GrinningGrandad

As Hutch said, your make and modelyear of caravan will help folk on here be more able to help you.

Anseo

 

[GrinningGrandad]

Apologies, we have purchased a new Elddis Xplore 304. I think I am slowly getting my head around it now. Put the sub pump in the aqua roll, turn on the main 12v pump supply, open the hot water tap, pressure switch will kick in and tell pump to to fill tank until it runs out of the tap. Close tap (pressure switch tells pump to stop). Repeat with cold tap. Every subsequent opening of taps will reduce pressure and pressure switch will start the pump. I’m hoping this is correct even though it sounds obvious and make me look foolish. In my defence the manual only tells you what to do to get water, not how it works and it was only when I found a small label amongst all the literature that I saw I Whale IC Pump Controller had been installed and, researching that made it a lot more clearer.

 

[Hutch]

GG, don't worry, we have all had times that we couldn't get our heads around things, last year before a trip out I kept blowing the water pump fuse, I forgot the obvious, the water pump had seized up.
I hope its all working for you.

 

[audiorob]

I have a similar Elddis model.
Drop the pump in the aquaroll. Leave the water heater switched off. Ensure the drain valve is closed (under the front bench near the heater - largish yellow lever!) Switch on the water pump at the control panel. Start with the tap furthest from the inlet and run the hot until it runs smoothly without spluttering. Then the next tap the same, then the last. Now repeat with the cold. This runs out any potential air-locks and fills the system.Then you can switch the water heater on.
To save towing water home, switch off the water heater in good time, to allow to cool. Then open the drain valve, then open all the taps, centrally so that both hot and cold will drain. The water will empty onto the pitch and as you drive home. This is the same drainage procedure for winter lay-up.
You may need to adjust the pressure sensor on the back of the inlet - https://www.whalepumps.com/rv/siteFiles/resources/docs/resource-library/WhaleAdjustingyourpressureswitchb.pdf
is worth printing - step by step instructions from Whale. You will find that you have to re-adjust slightly between mains power and battery power.

 

[GrinningGrandad]

Thank you for this, I was going to ask whether you needed to drain the tank or not so you have answered this questing too.

 

[ProfJohnL]

It seems you have understood the operation of the pump through the pressure switch, but here a bit more information about the water system and heater.

Just after the cold water comes through the pressure switch, the pipe will split: one side feeds all the cold taps, and the other side goes to the water heater. The water heater is a storage type, and it consists of a tank with a cold water inlet at the bottom and a hot water outlet near the top. There is a non return valve on the inlet which prevents the content of the tank from draining back into the cold supply pipe but also it prevents the higher pressure of a heated tank from backfeeding the supply pipes.
When a tank of water is heated, the hottest water collects at the top of the tank. That's why the outlet is near but not actually at the top. This is to ensure the tank has a small air pocket to act as and expansion space when the water heats up.

With this arrangement, once the tank is filled, it will remain filled, and to get hot water out, you must push cold water in at the bottom.

These heaters are also fitted with drain valves that allow the heater to drain despite the inlets non return valve. draining is important especially during winter storage, as freezing conditions will damage the heater. It also sensible to drain the heater to reduce weight tow towing, and to reduce the load in the tank which may damage the heater if it sloshes around too much when towing.

 

[GrinningGrandad]

Thanks for this Prof, I do like to know how things work not just that they do work and this explains things nicely in layman terms.
I have to say that being new to caravanning, the willingness of people to help and provide advice is heartening.

 

[RayS]

Only part of this thread I'm not too happy about is the suggestion to drain the system onto your pitch before moving off. The system will contain around 15 litres of water, enough to make quite a muddy spot on a grass pitch to the discomfort of the next occupant. Further, since most caravans will have the drain in more or less the same place, mass use of this idea will make the problem worse. Also, the heater is pretty well insulated so unless you remember to switch it off well in advance the water may be hot enough to damage the grass.
Even on a hardstanding pitch I would not be too happy to paddle about in surface water when setting up.

Suggest that if you follow this advice you find a convenient sufrace drain or gutter to receive the water.

 

[Craigyoung]

I have just left a site in Yorkshire at 2 p.m. this afternoon and like you said that you were not happy about but I dropped my water onto the gravel pitch , it took a few minutes to drain out and as I was spinning the caravan round on the mover and as I hitched up , the water had evaporated and gone and drained into the stones , no harm done at all ?
I agree dropping hot water on the grass may harm it which I don't do , I always wait till im hitched up and on solid ground before I dump the water .

 

[Anseo]

No qualms here about discharging tepid water onto the grass or the ground, some sites encourage waste water to be disharged to hedgerows etc.

The water will soon drain away, the Rain God discharges many hundreds of litres per day onto the grass etc.