We have a sealed CH system with separate programming for ground-floor radiators, first-floor radiators, and domestic hot water.
We recently had a very small radiator fitted in our very small downstairs toilet, and — presumably because it was most convenient for him — the plumber connected it to the DHW. That is, the radiator is connected to the hot water tank by two quite short horizontal 15mm pipes.
The problem is that this radiator does not heat up, except when the tank thermostat has closed and triggered the DHW motorised valve, so that the pump and boiler come on. But as soon as the tank thermostat opens again, switching the pump and boiler off, the radiator rapidly cools down. The result is that it is warm only for a short period in the middle of the night! The rest of the time, we have a tank of hot water and a cold radiator, without any movement of water between the two.
People tell me that the radiator should be removed from the DHW pipe circuit and reconnected to one of the central heating pipe circuits. I'm looking for a simpler alternative, though.
To move water between the hot tank and the radiator, why not a separate pump, fitted in one of those short horizontal pipes? Electrically it could be driven by the live wire coming from the hot water programmer, via a wall thermostat to be installed in the small toilet. But what sort of pump? It should connect to 15mm piping, would be active for short periods only, would need to pump only the capacity of the radiator each time, through a short length of piping, with no gravity to overcome. Or is this a crazy idea (if so, why?)
Thanks for your thoughts on this suggestion.
We recently had a very small radiator fitted in our very small downstairs toilet, and — presumably because it was most convenient for him — the plumber connected it to the DHW. That is, the radiator is connected to the hot water tank by two quite short horizontal 15mm pipes.
The problem is that this radiator does not heat up, except when the tank thermostat has closed and triggered the DHW motorised valve, so that the pump and boiler come on. But as soon as the tank thermostat opens again, switching the pump and boiler off, the radiator rapidly cools down. The result is that it is warm only for a short period in the middle of the night! The rest of the time, we have a tank of hot water and a cold radiator, without any movement of water between the two.
People tell me that the radiator should be removed from the DHW pipe circuit and reconnected to one of the central heating pipe circuits. I'm looking for a simpler alternative, though.
To move water between the hot tank and the radiator, why not a separate pump, fitted in one of those short horizontal pipes? Electrically it could be driven by the live wire coming from the hot water programmer, via a wall thermostat to be installed in the small toilet. But what sort of pump? It should connect to 15mm piping, would be active for short periods only, would need to pump only the capacity of the radiator each time, through a short length of piping, with no gravity to overcome. Or is this a crazy idea (if so, why?)
Thanks for your thoughts on this suggestion.