the old farmer where i keep my van has just given me a brand new "crownette major" 3kw water heater.still in box priced £15/ 1shilling and sixpence (i kid you not) its a nice looking bit of kit. works off rising mains or gravity my question to all you brainiacs out there is i need to convert my cold tap (somehow) so that when i turn the cold tap on the microswitch chimes in to switch on the pump and i get the flow to go through the heater unit any ideas how best to acheive this without it looking heath robinson-- ken
if your pump works on a pressure switch (i.e when the pump pumps the back pressure switches it off (rather than a micro switch on the tap) then you shouldnt have a problem ,all the heater will be is a continuation of the cold feed to the hot tap. BUT if your heater (and a juicy one electric wise) isnt a sealed one then your pump will happily run till it empties your tank through whatever holes it finds in the heater.
if the heater has some sort of pressure release valve (for safety reasons) if it realeases at a lower pressure than the pumps pressure again it will encourage your pump into a frenzy of tank emptying.
you will ofcourse have to wire the beast with heavy wire to a suitable trip on your mains fuseboard and make sure it has a very good earth.
a hot tap with a microswitch in tandem with your cold one will work ,the water will flow whatever tap is opened
just had a thought what if i just have an ordinary on/off switch as it is only a12 volt pump as per a car switch. first i hit the switch to on/this would start the pump and start the water flow then the sysrtem would charge and hey presto hot/cold water cant see any need for a micro switch ?? i can then hit the switch to off to stop the pump
sounds like you people know your electrics so i gather it is probably a no no then. on an aside we have always used a home leccy kettle for years now and have never tripped out the electric on sites