I have a conventional 'wet' central heating system with radiators in each
room fed from a wall mounted boiler in the garage. The boiler also heats the
water via an indirect cylinder. There is a thermostat on the hot water tank
which controls a motorised valve thus shutting off the supply to the tank
when set temp is reached. There is a room thermostat in the hall that
controls (I believe) the pump located near to the boiler. The room
thermostat has a terrible lag on it and room temperature tends to get too
hot and then too cold waiting for the stat to switch. I have put TRV's on
the radiators in my lounge/dining room which have improved things somewhat -
but in order to keep a hot supply feeding to these radiators I have to keep
the room stat high which then overheats the rest of the house! I am now
considering putting TRV's on all radiators apart from the bathroom (to allow
for at least one 'by-pass'). One question: If after carrying out this work I
then leave the room thermostat set high, will this result in the pump
running virtually permanently, and if so is this likely to cause any
problems?

Kev