I have just purchased a house builtin the 1920's. The CH system was apparently installed in 1987 - although a new-ish boiler since then (Ideal RS55). The system works like this: There is a header tank in the loft, the main radiators are pumped but the hot water and bathroom radiator are on a gravity feed. There is no thermostat on the hot water tank. The programmer only allows the heating to be on if the water is also on (fair enough!).
This gravity feed to the bathroom radiator is the pain in my butt right now. The original radiator was dented and corroded at the valves, it was a very small rad 500x400, so I swapped it out for one which is slightly bigger at 700x500. The problem is that whilst the ugly, leaky old radiator got reasonably warm, the nice new radiator is now luke warm. I have bled and bled but to no avail. However, if I switch the heating to the rest of the house off (i.e. hot water only on) it gets very warm indeed.
Example: bedroom 3 radiator gets to 45c degrees, the bathroom 31c - big difference
This suggests to me that the gravity feed to the hotwater & radiator is not 'strong' enough (if that's the right word) to cope with this slightly bigger radiator - so what are my options?
In a way I rather like the idea of this radiator coming on with the water because you might need bathroom heating in early/late summer but not the full house central heating, so I don't want to connect the radiator to a primary flow unless that's my only option.
This gravity feed to the bathroom radiator is the pain in my butt right now. The original radiator was dented and corroded at the valves, it was a very small rad 500x400, so I swapped it out for one which is slightly bigger at 700x500. The problem is that whilst the ugly, leaky old radiator got reasonably warm, the nice new radiator is now luke warm. I have bled and bled but to no avail. However, if I switch the heating to the rest of the house off (i.e. hot water only on) it gets very warm indeed.
Example: bedroom 3 radiator gets to 45c degrees, the bathroom 31c - big difference
This suggests to me that the gravity feed to the hotwater & radiator is not 'strong' enough (if that's the right word) to cope with this slightly bigger radiator - so what are my options?
In a way I rather like the idea of this radiator coming on with the water because you might need bathroom heating in early/late summer but not the full house central heating, so I don't want to connect the radiator to a primary flow unless that's my only option.