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Last seen: Apr 29, 2025
@derek-m Testing Grundfos motors I have connected a Pulse generator to find out if one of my GRUNDFOS motors is working. I varied the Pulse width ...
@iancalderbank Hi Ian, Your system seems a lot more up to date than mine. My Grundfos motors still has LEDs .which do not show that the PWM sys...
@iancalderbank I know , Ian, I am confused myself......... So here is latest on the PWM sage......... My Grundfos motors work under PWM when fe...
@iancalderbank Hi Ian More revelations about the Grundfos PWM Motors! I have connected my oscillator (to the Brown(Sig) and blue(Ref)) wires an...
@iancalderbank Hi ian, In frustration I have connected a Wave generator only to discover that you are right. The Wiring shown in the manuals is w...
@dandee Many thanks ......again I am astonished with the information about the SIG and REF inputs............. specifically , How have you connec...
@iancalderbank Hi Ian. Following my trumpeting of my apparent success in correcting the losses in my heat pump I have to admit that the supposed ...
Hi Graham, Believe it or not but I agree with you ! Having looked over the last year at the poor , incompetent , support I have had from my "insta...
@william1066 THE PWMI have finally got a "hopefully working PWM Motor controlling the Motor Speed to control the Water Heat Power. The Critical p...
@mike-h PWM Signals producing E912 errors when Not in use! I have been recording the PWM Signals presented to my GRUNDFOSS MOTORS. When supplying ...
@mike-h World record for Hyper-Cycling! Have a look at my Hyper-Cycling SAMSUNG HEAT PUMP. I make it 94 cycles in one day! Can anyone ...
Sorry William, I found the PWM Flow rate on page 58 of my new manual. Many thanks also to Graham , the new version of the manual at 208 pages is inf...
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Degrees of Separation
Latest Posts
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RE: New Vaillant Arotherm controls link to existing thermostats ; wired vs wireless
Floor plan of ground floor enclosed; Apologies for the ...
By GutoFfowc , 6 minutes ago
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RE: Cooling with air to water heat pumps
Passive cooling should always be the first call. Keep ...
By JamesPa , 53 minutes ago
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RE: How Accurate Is My DIY Heat Loss Calculation?
I think this calculation goes the other way. 3.54kW ga...
By JamesPa , 1 hour ago
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RE: Do I add Air Con or MVHR to existing A2W ASHP?
@rob-of-york Thank you, I’m thinking along these same l...
By Toodles , 17 hours ago
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@Mars Good questions! The downstairs unit did the maj...
By Rob of York , 17 hours ago
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RE: Questions about A2A for heating as well as cooling
@donciccio I would suggest that you take a "fabric-fi...
By Rob of York , 18 hours ago
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RE: Volumisers in Heat Pump Systems: Does Placement Matter?
@dave, I think @jamespa has probably identified the mos...
By Mars , 1 day ago
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RE: Plug and play solar. Thoughts?
My thought is simple. Bring it on and bring on plug in...
By JamesPa , 2 days ago
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RE: Heat Geek mini store vs pump size
Yes I agree, that’s why Heat Geek have most likely sele...
By Tomtheheatingengineer , 3 days ago
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RE: Who's your electricity provider and what's your tariff?
@chandykris Swings and Roundabouts, you win some…. ...
By Toodles , 3 days ago
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@tomtheheatingengineer, thank you, and welcome to the f...
By Mars , 3 days ago
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RE: HeatGeek vs Octopus surveys: puzzling disparity - any ideas why?
@majordennisbloodnok @tomtheheatingengineer For my ...
By JamesPa , 3 days ago
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RE: Is the "divide by 2900" rule still valid?
Really flow rate is a pipework limitation not a water p...
By JamesPa , 4 days ago



