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Last seen: Mar 16, 2026
@bn06amp my secondary pump is the Grundfos UPS3:130 which gives me 1.6m3/h (26l/min) at about 5m head set to maximum speed/curve. The primary pump in ...
For a typical 5degK delta T between flow and return, to provide 11kW you ideally need 11/(5x4.2) = 0.524l/s or 31l/min. Suggest the flow needs to incr...
@bn06amp ah, having the secondary hot water pump on a timer is a good idea, to only use when needed. You're right about the ASHP and hot water demand,...
@bn06amp yes, with a thermometer (you can buy little digital ones with small probes) check the temperatures are comparable across the top pipes and th...
@soniks thanks for that, the in-built pump in the Grant Aerona 17kW can provide 50l/min at 5m head on the highest speed setting. A Wilo Pico RP25/80 i...
@hughf EBAC make a decent UK washing machine, we have one, it's got an impressive 10year warranty. Not the most refined machine on the market but very...
Hi Ash, welcome. Underfloor has a lot of thermal lag, it will take a day or so to get the thermal mass up to temperature. You should be able to get aw...
Hi Jon, we're all looking at our smart meters and wincing right now. The outdoor temperature is close on 10degC below seasonal average, so ASHPs are s...
@soniks have you details of the second circulation pump fitted? Maybe a photo or something? Have you a flow setter / gauge on the system or any way of...
@soniks That's useful stuff. Is the 44deC supply typical? The 12degK between your supply and return water temperatures is revealing. That suggests to ...
@cathoderay Yes, understood. My home heat loss estimate for the current weather averaging -1degC outdoor air temperature is 6kW or 144kWh per day. Add...
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RE: Electricity price predictions
@jamespa Yes another missed opportunity yesterday, b...
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Well those are "MC4" plugs and sockets. Yes the ones ...
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Hah! Well I guess we're all in the realm of conjectu...
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These are a bit hard to read but the information is in ...
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RE: Octopus Cosy Heat Pump Owners & Discussion Thread
Ah, not so useful then For sure, hopefully before ...
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Thanks @editor I appreciate that things go wrong, bu...
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RE: Seeking ideas / information / commiseration - Pure Drive
@little-lights If I understand you correctly your syste...
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RE: Home energy storage & battery register
AC coupled Pure Drive 10kW battery Solar PV Solis P...
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RE: Rate the quality of your heat pump design and installation
@claireisamazing, that’s got to be one of the most posi...
By Mars , 19 hours ago
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@jamespa Great, thanks - I've had a quick look at the a...
By Little Lights , 21 hours ago
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RE: Air source heat pump roll call – what heat pump brand and model do you have?
Forum Handle: ispookie666 Manufacturer: Vaillant Mo...
By ispookie666 , 22 hours ago
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RE: A2A vs A2W: Which Heat Pump Would You Pick?
I'm fairly new to the forum and have not voted. Back...
By ispookie666 , 22 hours ago
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I am seeing an increasing number of occasions when my G...
By DavidAlgarve , 23 hours ago
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RE: End-of-Life Heat Pumps: How Do You Dispose of an ASHP in the UK?
@editor Thanks Mars. I look forward to the subsequent ...
By DavidB , 1 day ago
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RE: Anyone concerned about GivEnergy?
Fair enough. Its interesting that opentherm (for boil...
By JamesPa , 1 day ago
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RE: Brand and installer questions for ASHP
A tank solely in the return (upstream of where the retu...
By JamesPa , 1 day ago
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RE: UK DIY Battery: SEPLOS 48V 200Ah x2 + Sunsynk 8K – Safe Installation for Garage Conversion
thank you to all who have already replied. I have been...
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RE: Home automation and the cloud; is there a better way?
+1 It's not just cloud though. Many devices have repla...
By bobflux , 2 days ago
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RE: Summer usage. Why is my Vaillant Aerotherm using so much energy on "heating"?
So the red bars are 'DHW' and the yellow bars 'heating'...
By JamesPa , 2 days ago
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RE: Indevolt Batteries UK Support & Info Thread
Have you tried cutting the grid feed to see what actual...
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RE: Renewables & Heat Pumps in the News
Critics and naysayers will be negative whatever the gov...
By JamesPa , 2 days ago
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RE: Microbore heat pump installs
In principle you are almost certainly right, but in pra...
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RE: What is the main ‘dictator’ of Agile’s unit price?
@toodles I keep an eye on wholesale prices and energy m...
By ChandyKris , 3 days ago
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RE: Upgrading my system, how far do I go?
For comparison, my PW3 with 11.04kW inverter, will char...
By Old_Scientist , 3 days ago

