Confused..Just bought a property , not got combi boiler , but Tank upstairs, Kitchen Hot water works fine , bath hot water works fine ,basin in the bathroom hot water comes out luke warm unless i run the cold tap and then the hot seems 2 work better, has no electrical shower but one i think that just works from cold feed & hot shud be from boiler tank(looks like one of those old showers at school) ,the shower has a thermostat on it with just Hot arrow & cold arrow, but when u turn the shower on nothing but cold water ..ene info wud be appreciated .