I HAD AN ELECTRIC BOILER WITH UNVENTED HOT WATER CYLINDER INSTALLED LAST YEAR..I HAVENT HAD ANY HOT WATER EXCEPT WHEN I PRESS BOOST BUTTON..AFTER LEAFING THROUGH THE LITERATURE THAT CAME WITH IT I CAN SEE THAT IT SHOULD REALLY HAVE BEEN CONNECTED TO AN ECONOMY SEVEN/TEN METER TO MAKE THE MOST OF CHEAPER RATES..HOWEVER I DONT HAVE ONE AND THE PEOPLE WHO INSTALLED IT DIDNT ADVISE...IF I GET ONE INSTALLED CAN I GET THE BOILER CONNECTED UP RETROPSEPCTIVELY AND WITHOUT INCURRING TOO MUCH EXPENSE..I SHOULD HAVE THOUGHT ABOUT THIS MORE BEFORE I HAD IT INSTALLED BUT IT WOULD HAVE BEEN HELPFULL IF I'D BEEN ADVISED BY THE INSTALLER BEFORE THEY WENT AHEAD...PLEASE COULD SOMEONE HELP..THANKYOU
