Anyone know why this is rated "not suitable
for bath". Is it just that the flow rate is low, so it would take an age
to fill, or is it that it can't run continuously for long enough, or
maybe some other reason?
 currently looking for an emergency solution, so an age to fill isn't
necessarily an issue.
It's just the age-to-fill issue. I've got a 27kW combi, and a small
bath, and that's just about bearable. Even the 12kW version of this
electric heater would take over twice as long as my boiler. I don't
know what the rate of heat loss from a large shallow body of water
open to the air is, but over the time it would take to fill you'd be
struggling to get it beyond tepid.
We used to have a Mains Severn (?) and it was very efficient at filling a
bath with hotter water than needed.
The one you feature does say, "Allows you to supply up to 2 basins or 1
basin & 1 shower with instant hot water" which isn't suitable for a bath :-)
I really don't know:
I've been happily using the 9.5-kW version for DHW for eleven years.
It takes me about 17 minutes to run a bath, but I do fit in quite snugly!
I have forgotten a couple of times and run it for over 40 mins, without
Martin Pentreath wrote
Anglia Water suggests that an average bath water usage is 80l so it
would take around 20minutes to fill. The water final water temperature
needs to be around 38C to feel comfortable for a toddler so for an adult
it probably needs to be a bit hotter.
In article ,
"Mary Fisher" writes:
Main (now part of Baxi/Potterton) produced a whole range of these
over many years. I inherited a Main Medina when I bought a house
which eventually wrecked itself about 8 years ago (see humour pages
of the FAQ) and I replaced it with the then current one with
thermostatic control, Main Medway...
brilliant and fills a bath in no time at all.
Still works when electricity goes off (I don't think that's true
of the current model anymore).
Sorry, no, nor a thermometer...
Timed it tonight at 19 mins. Perfect! Just below the overflow with me in,
with no additional cold required.
(Incoming water must be getting colder. Next stage is to turn the tap down
slightly when it's really cold.)
Forgot to mention that the input pipe is plastic, allowing some expansion?
and output pipe is microbore, replacing some truly grotty old lead plumbing
and giving the water chance to reach the tap before it's gone cold!
Cable is 6mm**2, part clipped direct, part plastered over and gets barely
The lights dim a bit, but they also do that throughout the evening when
anyone else on our street on this phase uses an electric shower...
The house had a pre-WWII cylinder with tank just above, all in the back
bedroom, heated (well, just the top 1/3) by (1950s?) immersion, the old coal
back-boiler being unusable because of the gas fire and being in a smokeless
The Powerstream was originally installed to give a shower and run the
bathroom handbasin, but once I'd found that the bath could be filled OK
using the shower, and the temperature could be increased enough to do
washing-up by turning the tap down once the unit had fired up, the old junk
I don't know why they aren't more popular. Particularly now more powerful
ones are available.
(I would have liked a gas multipoint, but there's really nowhere convenient
to install one. Or even a combi-boiler and central heating one day, but I
like my old gas fires and British Gas keep offering me central heating
service contracts which would cost more than my energy bills! This thing has
cost nothing in maintenance for 11 years.)
Ours was, in fact the present boiler is too, fitted to the kitchen outside
wall, high enough not to be noticed but serviceable from a step ladder. I
thought they always had to be on the floor but Spouse said no and put it up
There's nothing to stop you having a boiler AND gas fires, we do.
In message , Martin Crossley
Yes, I had one like that, when I took it out turned out one reason was
that it was about 50% full of limescale, in big chunks that had fallen
off the walls of the cylinder over the years
In article ,
"Mary Fisher" writes:
The "Main" ones could only go on a wall -- they hang from the
through-the-wall balanced flue. Main actually went to some effort
to ensure the newer ones could be hung from the flues of the
earlier models, which made replacement much easier as you didn't
have to change the flue.
I kept 2 out of 3 of my gas fires and the multipoint when I
put the boiler and central heating in. The boiler only does the
central heating, and the multipoint continues to do the hot water.
The gas fires are decorative in one case, and a backup in the other.
(The 3rd one was at end of it's life and thus went.)
Well, having finally got someone to quote and date it maybe goes to the
back burner .... once again.
That's OK, stacks of them in the loft, if I shovel them out it's two
jobs done in one.
I've no idea about 'Main' brands.
We did the same. We retired the multipoint when we installed solar water
heating, the new boiler is for ch everywhere except sitting and dining
rooms, and boost to hot water on cold and overcast days.
There are usually several solutions to individual circumstances :-)
You could have kept the multi-point (see makers first, as some don't like
hot water acting on the diaphragms.) and had solar hot water feed the
multi-point. But you need a high pressure storage cylinder (unvented), or
use a thermal store at low pressure using a plate heat exchanger. Then
electric backup can be fitted in the cylinder. All with space permitting of
When the multi-point packs in get a Rinnai multi-point. But fit a flow
switch on the cold mains supply to it, switching out the boiler when DHW is
called to save overloading the meter. The flow rate is world away from a
Main with top reliability. You can have a remote control in the bath or
shower and raise or lower the temperature of the water suit.