Electric water heaters

[briwy]

Could someone enlighten me as to how these are piped and wired up please.

I assume that they are some form of immersion heater but ours has no

header tank so are they under mains pressure or what and how is

expansion taken care of?

All the houses we viewed and the one we eventually bought dont have any

timers on as is usual in the UK.  Is there any reason for this as

it seems a waste of power if they are just on all the time as ours

appears to be when the breaker is on.

Must say it works brilliantly and the house we have bought has just had

a new one but I would like to know how it works just in case of a

problem.

Thanks

Brian

[Cassis]

All under mains pressure, hence the wonderful shower pressure.

No expansion tank required.

Usually there is a switch for the boiler in the fuse/disjoncteur box with 3 settings - on, off and economy.  The latter just allows the chauffe-eau to heat during night hours (off peak rates).

[Nick Trollope]

[quote user="Cassis"]All under mains pressure, hence the wonderful shower pressure.

No expansion tank required.

Usually there is a switch for the boiler in the fuse/disjoncteur box with 3 settings - on, off and economy.  The latter just allows the chauffe-eau to heat during night hours (off peak rates).




[/quote]

Assuming you have the appropriate tarriff with EDF. No reason why you should not fit a timer if you want to.

& BTW, open water storage - as in header tanks are illegal in France. One more reason why French plumbing is so much better than UK plumbing.

DUCK!

 

 

[Cassis]

 [:D] [:D]  How wise to disappear under the parapet - but I think you may have got away with it, Nick! [:D]

As Nick says, the cheap night rates only apply if you have an "Heures Creuse" tariff. 

You pay slightly more for your standing charge with Heures Creuses compared to a basic tariff.

e.g.  6kva  with disjoncteur rating 30A is 105,87€ pa instead of 61,06€ pa.

but with Heures Creuses you get cheap leccy for 8 hours during the night

i.e.  0,1074€ per kwh standard daytime rate and 0,0654€ per kwh cheap night rate instead of all at 0,1074€.

So Heures Creuses can make sense if you have electric hot water heating and can set your washing machine, dishwasher etc. to come on during the cheap rate period.  Even more so if you have storage heaters.  The rates are correct as at 1 Dec 2006.

[Anton Redman]

Most have a rubber diaphram, as the Actress said to the Bishop., this swells/expands as the water heats up but they also have a presure valve which farts/drips if the expansion / presure becomes too great.

[briwy]

Thanks for the replies everyone.

I think we do we have the cheap tariff so I will see about fitting a timer.

[Cassis]

If your house is wired normally like ours then the Heures Creuses for your hot water heater do not work on a timer - there should be a "switch" on your fuse box for your hot water heater with three positions - off, permanently on (often marked by a "sun" symbol) and economy (often marked by a "moon" symbol); the latter automatically switches the heater on during night time cheap rate hours and off at other times.

[Gluestick]

Always seems to be some confusion about this one.

Heures Creuse applies to the whole supply, if you have the cheap rate, since it only a function of the compteure (meter), which measures consumption after cheap rate commences and when it finishes and logs power used between the On and Off times as one log: and all power used during other (Heures Pleine) times as the other.

My bill is thus in two parts: one charge for the power used during Heures Creuse and another for Heures Plein plus the abonnement.

The special switch for Ballons, e.g. is simply two parts. The first switches On and Off using a pulse sent down the line by EDF: on at circa Midnight and Off at circa 08.00AM.

The selector switch allows the user to choose, Off; or On permanently, or finally Pulse.

Thus when the selector switch is set to Pulse, the Pulse switchwill not enliven the Ballon circuit until the cheap (Heures Creuse) rate applies.

Nothing stopping you from wiring other appliances in the same way, however modern washing machines/diswashers often now have an inbuilt timer circuit whereby the user may select a time when the cheap rate applies, thus in this case it is not necessary.

Nick:

Why ought you to duck?

Most UK new and replacement plumbing now uses closed systems and combi-condensing boilers are increasingly the norm.

Gravity systems are, archaic and unhealthy: all that water festering away in an open storage tank. Yuk!