[H2GoKent]

I have a 3kw immersion heater in my 500litre tank.
What sort of temp rise will it give me per hour? I appreciate there are variables such as ambient temp., heat loss etc but even ball park figure would be useful.

Thanks in anticipation.

Used to know how to calculate it for air when I worked in air conditioning but that was a LONG time ago.

[richard jagger]

You need to insulate your tank.Then it is still very slow. also is it a 27 inch or a 11 inch element.Get your self a 1000  or a 500 watt fish tank heater to pre heat water so it will heat quicker on the boiler element. heat  heater. I bought a 500 watt alu/ heater of the e bay for 4.95 and this will cope with 500 litres. what I also do is stir the water from time to time to circulate heat.

[♠Winp®oClean♠]

I would advise NOT to insulate the tank- if you also want to keep the van frost free too (which is 50% of the benefit of an immersion).

The water will mix itself as soon as you drive off in the morning. The tank & water will stay nice & warm all day (surprisingly) in an uninsulated tank.

[H2GoKent]

Both useful replies, but I really wanted was some figures, normally there are some people with the requisite knowledge around...

I don't insulate my tank as this then warms the hoses and equipment keeps them frost free.
I did ponder the mixing problem, will it not mix a bit through convection, altho not perfectly of course.

[Window Washers]

I would advise NOT to insulate the tank- if you also want to keep the van frost free too (which is 50% of the benefit of an immersion).

The water will mix itself as soon as you drive off in the morning. The tank & water will stay nice & warm all day (surprisingly) in an uninsulated tank.

do you use this yourself ?

if so could you porvide a link to where to buy it from and how much it costs to run it ?

[♠Winp®oClean♠]

I would advise NOT to insulate the tank- if you also want to keep the van frost free too (which is 50% of the benefit of an immersion).

The water will mix itself as soon as you drive off in the morning. The tank & water will stay nice & warm all day (surprisingly) in an uninsulated tank.

do you use this yourself ?

if so could you porvide a link to where to buy it from and how much it costs to run it ?

If you go on matts forum there's a great thread called "immersion's going in" every drop of info you could wish for inc' pics & links to everything required is on there.

[♠Winp®oClean♠]

Both useful replies, but I really wanted was some figures, normally there are some people with the requisite knowledge around...

I don't insulate my tank as this then warms the hoses and equipment keeps them frost free.
I did ponder the mixing problem, will it not mix a bit through convection, altho not perfectly of course.

It does mix by convection yes. As in any similar situation (like a domestic hot water tank) the water will always be warmer at the top.

My tank is a 400ltr flat & the element is approx 1/3 to 1/4 from the bottom.