Undecided ... electric only

Reed_Richards

Energy28 said:

Reed_Richards said:

Energy28 said:

Would the hot water cylinder (117ltr) be big enough for 4 people to have showers? Do I need a different kind/ size of hot water cylinder? 

There are two types of hot water cylinder, vented and unvented.  In the case of the unvented type the water in the cylinder is pressurised so you don't need to worry about the head of water between the cylinder and the shower outlet.  Do all your cold taps deliver water at mains pressure?

Yes all high pressure 

If you have mains pressure cold water and a vented hot water cylinder it can be very difficult to balance the hot and cold flows to get the right temperature in the shower.  So I recommend you get an unvented hot water cylinder which means you also don't need to worry about the head of water.  It sounds as if you will need a bigger volume cylinder anyway. 

jbuchanangb

The type of shower can go over the bath or be in its on cubicle. Don't get one where the water is heated by electricity, use the water from the tank, but a power-shower uses water from the tank and uses electricity to pump the water creating a strong shower. It is possible to get such showers with automatic temperature control so that the shower adjusts the mix of hot and cold water to get the desired temperature.

[Deleted User]

Reed_Richards said:

Energy28 said:

Reed_Richards said:

Energy28 said:

Would the hot water cylinder (117ltr) be big enough for 4 people to have showers? Do I need a different kind/ size of hot water cylinder? 

There are two types of hot water cylinder, vented and unvented.  In the case of the unvented type the water in the cylinder is pressurised so you don't need to worry about the head of water between the cylinder and the shower outlet.  Do all your cold taps deliver water at mains pressure?

Yes all high pressure 

If you have mains pressure cold water and a vented hot water cylinder it can be very difficult to balance the hot and cold flows to get the right temperature in the shower.  So I recommend you get an unvented hot water cylinder which means you also don't need to worry about the head of water.  It sounds as if you will need a bigger volume cylinder anyway. 

It’s quite easy to balance hot and cold water pressures if the plumber installs a balanced flow valve in an unvented system. They cost about  £50.

https://heatingpartswarehouse.co.uk/product/caleffi-22mm-cold-water-control-valve-3-6-bar/?gclid=EAIaIQobChMIiceb0saK8gIVwbTtCh10PQ4VEAQYASABEgK7y_D_BwE

Reed_Richards

[Deleted User] said:

It’s quite easy to balance hot and cold water pressures if the plumber installs a balanced flow valve in an unvented system. They cost about  £50.

https://heatingpartswarehouse.co.uk/product/caleffi-22mm-cold-water-control-valve-3-6-bar/?gclid=EAIaIQobChMIiceb0saK8gIVwbTtCh10PQ4VEAQYASABEgK7y_D_BwE

As far as I can see, a "balanced flow valve" works by reducing the pressure of the cold water to match that of the hot.  This would be fine if the hot water cylinder provides a good head of water and thus a decent pressure but would it be adequate otherwise or would the flow rate be too small for a decent shower?

QrizB

Not exactly moneysaving* but I have a vented DHW tank with mains-pressure cold water. The previous owner fitted a pumped mixer shower (an Aqualisa Quartz, other makes/models are available) and it copes admirably.

We have a 42x16 tank (about the same size as the OP) and it can cope with two showers, three if you're careful.

Why not moneysaving? Well the shower is £600-ish to buy and uses quite a lot of water. It's very pleasant, though

Reed_Richards

About 25 years ago I briefly had a pumped "Power Shower" before I fitted an unvented cylinder and made it redundant.  It was incredibly noisy; you certainly could not sleep through it being used.  Have they improved since then?  

QrizB

My processor (pump and thermo mixer device) is in the loft space, pretty much over the shower. You can hear it but I wouldn't describe it as "incredibly noisy". It's fairly low pitched hum, noticeable but not intrusive IMHO.

macman

£2k pa for a mid-terrace (guessing 3 b/r)? Ouch! Have you looked at switching to a competitive E7 tariff and ditching the E10? Are those extra 3 hours really crucial?

QrizB

Energy28 said:

We are with EON E10 22.5p peak and 13p off peak.

As macman says, that's not a great tariff.

There are even single-rate tariffs available around 15p. Depending on your split between peak and off-peak consumption you might be better off on one of those. And that's without looking into smart ToU tariffs like Octopus Go.

Energy28

Energy28 said:

Reed_Richards said:

Energy28 said:

Would the hot water cylinder (117ltr) be big enough for 4 people to have showers? Do I need a different kind/ size of hot water cylinder? 

There are two types of hot water cylinder, vented and unvented.  In the case of the unvented type the water in the cylinder is pressurised so you don't need to worry about the head of water between the cylinder and the shower outlet.  Do all your cold taps deliver water at mains pressure?

Yes all high pressure 

Hi

I spoke to a plumber and he agreed with you that maybe I need an un vented direct cylinder working at mains pressure and a larger tank. He suggested 180 or 210 litres. Do you think that these sound about a good size?