Electric shower v using combi boiler hot water - most efficient way to set it up?

BooJewels

QrizB said:

BooJewels said:

My numbers today suggest that it's pretty much break even - not quite the 'ditch electric showers' mantra often posted here for people wanting to reduce electricity bills.

There are some rough calculations here; saving a notional 7p/shower isn't going to make a huge dent in anyone's bill.

Thanks for that.  I notice that those calcs include both water and waste water costs, but I had been thinking that there's also some electricity used by your boiler, pumping the water to the shower, adding to it too.  I had what seemed to be a higher than expected electric meter reading this morning, thinking that was it - but just looking at the spec for the boiler, mine seems to be 87watts maximum - so that's not going to trouble the meter in a handful of minutes - so it looks like I was wide of the mark in that part of my thinking. 

As I'm not metered for water, for me, at least, there's only the gas that has a direct cost element.  For those that are metered, the higher flow rate from a combi boiler, using more water, makes the difference even less.

markin

northernsoul said:

markin said:

Do you use a timer to always get a 8min showers?

northernsoul said:

Why have my spreadsheets been deleted. Is it against the rules ?

Probably auto deleted by the forum software, where did you host them?

I use a timer up to 6 minutes.
My spreadsheets were a screenshot of my online excel spreadsheets. Do not know how to copy a file from online excel (probably would have been worse doing this though - more personal information)

I use imgur to host photos, and you have to use the forum buttons, not BBcode, The are some hosts that are banned.

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When we are talking pennies you really need to do a timed test to get data. Mixer taps are around £100? 2 none return valves £20? And an hr for a plumber if you can't DIY it.

You could T the hot pipe into the cold feed for the electric shower, none return valve needed, Then if it heats it at all its just raising it 5c? Crazy idea?

BooJewels

markin said:

northernsoul said:

markin said:

Do you use a timer to always get a 8min showers?

northernsoul said:

Why have my spreadsheets been deleted. Is it against the rules ?

Probably auto deleted by the forum software, where did you host them?

I use a timer up to 6 minutes.
My spreadsheets were a screenshot of my online excel spreadsheets. Do not know how to copy a file from online excel (probably would have been worse doing this though - more personal information)

When we are talking pennies you really need to do a timed test to get data. Mixer taps are around £100? 2 none return valves £20? And an hr for a plumber if you can't DIY it.

You could T the hot pipe into the cold feed for the electric shower, none return valve needed, Then if it heats it at all its just raising it 5c? Crazy idea?

Is that addressed to me?  If I were publishing a technical paper, then accuracy would be vital - I just wanted to see how much it would cost to 'take a shower'.

I tried again this morning - thinking that I'd reduced the water temperature from the boiler - but it transpired I hadn't done it right and it had reverted to 55C.  Did watch the clock for 8 minutes (not a digital timer, so not that accurate) and it was much the same gas use as yesterday - 0.288 m3 = 3.25kWh = 24p.  There are too many variables to be too accurate anyway - how much you turn the tap on/flow rate, starting temperature of the cold water, if you'd just run hot water, so warm came through faster etc etc.  I think I've scratched my own personal itch about the potential saving and will continue as I was - it's simply not energy saving enough to be worth making any changes just now.  But I do need to address the very dated bathroom at some point, so it will be addressed then.

If nothing else, the hose shower position being different over the bath than my electric shower head must have found a spot where the seal around the bath, or between tiles, must be failing and I came downstairs to a wet kitchen and spoiled ceiling.

On the plus side - it was a much better shower - hotter and much more pressure and flow, so more enjoyable and I will use my hose extension for hair washing etc which was what I got it for. So, other than a damp ceiling and time wasted mopping up, nothing lost by experimenting.  At least, now I know the answer.

northernstar007

got my shower running off the combi worcester, never go back to anything else, have 1 every morning 10mins max and worth every penny 
btw water in the winter coming in ice cold, combi dosnt flinch

BooJewels

There's no two ways about it @northernstar007 the quality of the shower itself was certainly better and I very much enjoyed them - but the saving in itself can't justify the work that needs to be done - until I get other upgrades in the bathroom done too.  

It's just a shame that my bath taps are at the wrong end of the bath to use this push on hose more long term - because it seems to work well enough.  At least I know for certain that the boiler is easily up to the task.

Perhaps the most pressing issue is to figure out where the leak occurred and get some silicone in there.  Yet another thing I need to learn how to do.