Hi,
I'm looking for some advice, perhaps I should give some background first to hopefully make the situation easier to understand.
I am helping renovate a bungalow for my parents and as part of this I need to sort out a hot water solution for them. It is a 2 bed, detached bungalow, heating is sorted but need a solution to supply a kitchen sink, basin and thermostatic mixer shower that is part of a shower cabin (ie. the shower mixer cannot be substituted and an electric shower is also not viable).
A gas combi is obvious but we have been quoted £16,000 for connection, so that's a no-go. LPG is also out due to the regulations regarding tank location and the layout of the property (been down this route with the council planning already). Ground-source heatpumps are too expensive in regards to initial outlay, so although I understand the running costs are high I was thinking of instantaneous electric units (OK an unvented cylinder / thermal store would be a reasonable choice but space is a premium and if we can avoid the associated costs we'd prefer to).
Some basic flow rate measurements from a mixer tap in the kitchen revealed about 4 litres per min hot from the immersion and 10 litres per minute from the cold feed. The supply to the house is 100 Amps, but the Electricity company can increase this to a max of 120A so that's a reasonable amount of headroom.
My idea (crazy though it may be) is to run a 9KW Redring Powerstream under the kitchen sink and a 12KW Powerstream 2m away from the shower. These would be connected via a relay that prevents both from heating at the same time. Now with just the two of them living in the bungalow this would not be an issue in practical terms, so it is whether a 12KW powerstream would generate enough pressure and flow rate to work with the termostatic mixer? (Again as there are only two persons living there the idea of heating water as you need is attractive as you'd might expect).
Now they aren't looking for power shower performance, so niagra falls is not needed
. I have no specification on the shower mixer, but suffice to say that on cold the mains pressure is far more than they need / looking for.
Now I know the Powerstream units will significantly reduce the flow rate (I reckon on about 5 litres per minute with average weather conditions) but will this still be enough pressure to allow the standard thermostatic mixer to provide a reasonable shower?
Does anyone have any thought, comments or experience regarding the above (aside from pay the £16k for gas, install an oil tank or use LPG bottles) or do we really have no option than to go with an indirect unvented cylinder or thermal store?
Thanks for your help
Tony
I'm looking for some advice, perhaps I should give some background first to hopefully make the situation easier to understand.
I am helping renovate a bungalow for my parents and as part of this I need to sort out a hot water solution for them. It is a 2 bed, detached bungalow, heating is sorted but need a solution to supply a kitchen sink, basin and thermostatic mixer shower that is part of a shower cabin (ie. the shower mixer cannot be substituted and an electric shower is also not viable).
A gas combi is obvious but we have been quoted £16,000 for connection, so that's a no-go. LPG is also out due to the regulations regarding tank location and the layout of the property (been down this route with the council planning already). Ground-source heatpumps are too expensive in regards to initial outlay, so although I understand the running costs are high I was thinking of instantaneous electric units (OK an unvented cylinder / thermal store would be a reasonable choice but space is a premium and if we can avoid the associated costs we'd prefer to).
Some basic flow rate measurements from a mixer tap in the kitchen revealed about 4 litres per min hot from the immersion and 10 litres per minute from the cold feed. The supply to the house is 100 Amps, but the Electricity company can increase this to a max of 120A so that's a reasonable amount of headroom.
My idea (crazy though it may be) is to run a 9KW Redring Powerstream under the kitchen sink and a 12KW Powerstream 2m away from the shower. These would be connected via a relay that prevents both from heating at the same time. Now with just the two of them living in the bungalow this would not be an issue in practical terms, so it is whether a 12KW powerstream would generate enough pressure and flow rate to work with the termostatic mixer? (Again as there are only two persons living there the idea of heating water as you need is attractive as you'd might expect).
Now they aren't looking for power shower performance, so niagra falls is not needed
. I have no specification on the shower mixer, but suffice to say that on cold the mains pressure is far more than they need / looking for. Now I know the Powerstream units will significantly reduce the flow rate (I reckon on about 5 litres per minute with average weather conditions) but will this still be enough pressure to allow the standard thermostatic mixer to provide a reasonable shower?
Does anyone have any thought, comments or experience regarding the above (aside from pay the £16k for gas, install an oil tank or use LPG bottles) or do we really have no option than to go with an indirect unvented cylinder or thermal store?
Thanks for your help
Tony
