Boiler - Loss of water

[Bioncy]

Have a Potterton boiler installed last november, onto an old central heating system. We have replaced two rads out of 6, and added thermostats on all but 1 radiator. I have had to top the water up a couple of times, but only when the heating system is on. Any idea's why the water pressure on the boiler keeps dropping, I've not noticed any leaking rads.

 

[namsag]

Tighten up all rad valves and check gland nuts under the caps

 

[stuarthall]

sealed systems do require topping up though now and again, due to water loss from evaporation, etc i believe...

 

[corgiman]

sealed systems do require topping up though now and again, due to water loss from evaporation, etc i believe...

Sorry stuart but your wrong. the whole point of a sealed system is that... well its sealed! and not open to the atmosphere, hence NO evaporation.

OP have you checked the drain off point that you used?

 

[undercover]

expansion vessel

 

[Agile]

Yes, but there is always a little loss of pressure from valve glands etc.

I always tell customers that topping up is needed every 1-6 months.

Tony

 

[gas4you]

Any more than every 6 months I would be looking for a problem somewhere.

Usually a slight top up each year at the service is all that is required.

 

[DP]

A well installed system will not need topping up other than possible pressure adjustment at annual service. At this point in time, pressure would be taken to zero anyway, to check expansion vessel and PRV.

 

[Bioncy]

A well installed system will not need topping up other than possible pressure adjustment at annual service. At this point in time, pressure would be taken to zero anyway, to check expansion vessel and PRV.

Thanks to all, I have been away so sorry for late thank you's. I think I may have a small leak from one of the valves, on the one radiator that we did not put a thermostat on !!!