My house is a 1970s build fairly well insulted detached 2 storey. Split in 2no zones which are controlled independently with digital thermostats and rarely run at the same time.
Downstairs has 9 double rads and 5 single rads.
Upstairs has 5 double rads and 1 single rad.
Open vent system std heat only oil condensing boiler 26kw.
About 10 years ago I swapped in a Grundfos Alpha 2 smart circulator pump. At the time this was in part due to radiator noise after installing TRV valves throughout the property and it did cure the noise.
Unfortunately I did not pay great attention to the balancing of the system. And only now when a new condensing oil std boiler has replaced the old one am I properly balancing the system again.
The pump is set to max constant speed 3 and showing about 38wattts power consumption on the display. Trouble is it does not seem to have nearly enough oomph to drive the heating system!
I noticed that of I turn most rads nearly off but still warm to touch I can get them all to show heat. But when I start to set the first ones to approx 11c drop across the other rads quickly die again and the boiler outlet pipe sits piping hot, return cool to touch and heat not going anywhere.
I think either the grundfos is starting to fail or I simply need a larger spec circulator pump in order to drive the water sufficiently around the house. Boiler located at one end of the house. 6 bedrooms house. So it has quite a path to go around.
Any recommendations for a replacement pump? Probably larger 180mm wide 8m head std unit not a smart one for a large property?
Downstairs has 9 double rads and 5 single rads.
Upstairs has 5 double rads and 1 single rad.
Open vent system std heat only oil condensing boiler 26kw.
About 10 years ago I swapped in a Grundfos Alpha 2 smart circulator pump. At the time this was in part due to radiator noise after installing TRV valves throughout the property and it did cure the noise.
Unfortunately I did not pay great attention to the balancing of the system. And only now when a new condensing oil std boiler has replaced the old one am I properly balancing the system again.
The pump is set to max constant speed 3 and showing about 38wattts power consumption on the display. Trouble is it does not seem to have nearly enough oomph to drive the heating system!
I noticed that of I turn most rads nearly off but still warm to touch I can get them all to show heat. But when I start to set the first ones to approx 11c drop across the other rads quickly die again and the boiler outlet pipe sits piping hot, return cool to touch and heat not going anywhere.
I think either the grundfos is starting to fail or I simply need a larger spec circulator pump in order to drive the water sufficiently around the house. Boiler located at one end of the house. 6 bedrooms house. So it has quite a path to go around.
Any recommendations for a replacement pump? Probably larger 180mm wide 8m head std unit not a smart one for a large property?