Hot water advice - Immersion Heater

Reed_Richards

Good news.  Save the immersion heater for when your boiler breaks down, hopefully never.

CinderKona

well it had other good stuff in there that will be useful at some point.

greyteam1959

CinderKona said:

well it had other good stuff in there that will be useful at some point.

Well I hope it is more accurate than the rubbish they gave you about the hot water cylinder.

[Deleted User]

matelodave said:

AS R_R says, the average tank should take around two to two and half hours from stone cold to heat to 60 degrees, a gas boiler will use around 6-7kwh of gas at 3p = 21p whereas the immersion will use about 6kwh at 15p = 90p.Therefore you dont want to use the immersion heater at all if you can help it.

It depends on the tariff. I am presently on Octopus Go (5p/kWh for 4 hours overnight). On an average day, my HW cylinder uses 7kWhs of gas to reheat the cylinder whereas my immersion heater uses just 3.5kWhs of electricity to do the same thing. Not only is gas less efficient than electricity but heat is lost as the flow moves around the house from boiler to cylinder coil. The difference in cost, for me, is marginal.

matelodave

Dolor said:

matelodave said:

AS R_R says, the average tank should take around two to two and half hours from stone cold to heat to 60 degrees, a gas boiler will use around 6-7kwh of gas at 3p = 21p whereas the immersion will use about 6kwh at 15p = 90p.Therefore you dont want to use the immersion heater at all if you can help it.

It depends on the tariff. I am presently on Octopus Go (5p/kWh for 4 hours overnight). On an average day, my HW cylinder uses 7kWhs of gas to reheat the cylinder whereas my immersion heater uses just 3.5kWhs of electricity to do the same thing. Not only is gas less efficient than electricity but heat is lost as the flow moves around the house from boiler to cylinder coil. The difference in cost, for me, is marginal.

I didn't really want to try and baffle the OP with the tecnicalities of different tariff structures or the thermodynamics and efficiencies of gas boilers, heat losses, tank heating coils, immersion heaters and other vagaries of heating systems - it just confuses the basic premis that, under normal circumstances gas is a lot cheaper than leccy (I could have chucked in the COP of heatpumps as well as E7 v E10, but it's not really relevant)

CinderKona

greyteam1959 said:

CinderKona said:

well it had other good stuff in there that will be useful at some point.

Well I hope it is more accurate than the rubbish they gave you about the hot water cylinder.

I am not sure what your point is - if you are a new buyer and in the absence of expertise, the homebuyer report at least offers a guide. Other items mentioned and that I will act on is advice on an extractor fan and lagging in the roof - which I did Saturday.