Water Heater usage

[Rubix]

Me being a newbie I have a (really silly) question about usage of the water heater.

Because of the conservation of power (ie not tripping the RCD on-site) I assumed that you would only turn on the water heater an hour or so before you were likely to have a shower or doing the washing up.

I read many posts on here about people leaving it overnight. Is that really necessary (I'm a secret lemonade ... midnight shower-er ) But is my idea of having to turn it on all the time a bit excessive ?

Your opinions please.

Thanks

 

[JeremyClarksson]

Generally we tend to leave ours on all the time even on gas.

The only time we turn it off on hookup is when we switch other high power items on i.e. at breakfast when toaster and kettle being used together a lot.

 

[LadyMo]

We leave our heater on all the time as well.The thermostat keeps it ticking over,so it isn't heating all the time.

 

[Wendy-Norfolk]

We leave our water heater on all the time too, although we can opt for 1kw or 2kw. Generally at this time of year we keep it on 1kw, which means we can use the toaster and kettle together if need be.

 

[Alexander_374295091]

We were woken the other night by the sound of our water pump, pumping constantly outside in the aquaroll, I got up and switched off the pump at our masterswitch, in the morning I went to check that the aquaroll wasn't empty and it was almost full, I turned on the pump and it ran for about 30 seconds then burnt out. It got me thinking what if one of the kids were to leave the hot tap running in the toilet and we went away out for the day and empty the aquaroll and drain the water heater. I thought it would probably damage the element in the water heater for that reason I now switch off the pump and water heater at bedtime and when we go out.

 

[Cockovan]

You cannot empty the water heater by leaving atap open. The pump pushes the water through the heater, when there is no more water to push through (ie aquaroll is empty) then the water heater remains full and nothing comes out of the tap.

 

[ProfJohnL]

Hello rubix,

You raise a valid point about energy conservation.

A water heater in a caravan is insulated and thermostatically controlled - so usually quite efficient. If we ignore the time and energy needed to heat the water from cold, and simply look at its maintenance rate, then you will find that the element is on for about 10% of the time. Over a day that is the equivalent of 2.4 hours.

Now! I have heard some caravanners say 'I've paid for the hook up so I'm going to us all the time and get my monies worth' and whilst that is one perspective, it is not a responsible attitude towards conservation.

I suggest an alternative approach would be coincident with your own, which is to plan your usage and turn the heater on about 40m to an hour before hand, and to turn it off again afterwards. This saves the 2.4 hours of maintenance power, and yet has it greatly inconvenienced you? - that is a matter of personal opinion.

This may seem contrary to advice I have given before about leaving heaters on, but the question was slightly different, usually 'is it safe to leave a heater on over night', the answer is yes, but it is not the most efficient use of the energy.

Similar arguments can be applied to space heaters. Fridges are a different and need to be kept properly cooled.

 

[Cockovan]

John,

obviously a lot depends on when you use hot water in your van as to whether your arguement is correct. We wash up 3 times a day, excluding showers, so we need hot water 3 times a day. If using your arguement of requiring up to an hour to heat up and use the water heater we would run it for 3 hours as opposed to 2.4hours if left on all day. Also by leaving it on all day you have hot water at any other time of the day for any other purpose. I beleive we get the best out of our water heater by leaving it on all the time at no cost to us or the environment.

 

[ProfJohnL]

Hello Alan,

Yes it does depend on your usage pattern, but I had considered that and in my second paragraph which is why I deliberately excluded the heat up from cold as that is an independent energy usage. I was only considering the maintenance rate - with no water draw off. As soon as you draw water from the tank, it introduces new cold water, so that is not maintenance, but reheat.

Even so, with your usage pattern, any time that you leave the heater on, but are not drawing hot water, and it goes through a reheat cycle, that energy is technically wasted.

 

[Rubix]

Thanks for your advice, I will probably leave it on most of the day, and probably turn it off at night.

Further to your comment John, about reheating. I suppose the heater in a caravan works in a similar way to an emersion heater in a house, in that a tank full of "hot" water is diluted by cold water when the "hot" water is drawn off, so it will then reheat if switched on, but if not on, will make the temperature "luke warm" until it is turned back on.

I was reading the technical info in the back of the caravan club site guide. It amused me as it has in their "setting up on pitch" info the last two points list turn on water heater then PUT THE KETTLE ON.

Me thinks with the heater and the kettle on at the same time ... POP goes the fuse !!! (best part of 10 Amps in my van !! Unless you have a gas kettle of course)

This was my reason for asking the question in the first place.

 

[ProfJohnL]

Hello again Rubix,

I tend to put the water heater on as soon as possible after arriving, then by the time we have the van fully set up we have hot water for washing.

As for the kettle, we only have a hob top kettle, then at least we can make a cuppa when we stop for rest.