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Last seen: Mar 21, 2026
Hi @derek-m The temperature difference of 1.5c is between Primary flow thermistor and Secondary flow thermistor. See sketch for positions and approx d...
@derek-m hi sorry I’ve spent one hour writing a reply to you and when I sent it it was lost without a trace. I can’t face re writing it again
Early test results showing opposite is happening in our system. I’ve opened up the primary pump valve until flow rate went up to 15 LPM (was 13) an...
Thanks @derek-m I will check the pump speeds. I recall the primary pump was adjusted to flow at 12 LPM but the secondary pump was left operating sligh...
@william1066 yes there’s are three sensors in total but only 2 are needed to activate the pump for the solar circuit. one is mounted in the roof top...
Another way I thought of checking efficiency was how long the DHW reheat took. Since there are less chances of cycling etc. So I set up a forced DHW...
@cathoderay great points and perfect timing. 👍
As @cathoderay says, there’s a lot of mixed feelings about the risks especially in an unvented system with high useage. It’s fascinating how how even ...
It looks like the Legionella routine is only calendar schedule driven with user selected options such as an adjustable 15 day cycle or less. Temperatu...
Hi @derek-m - you mean I could have got a free handout 😱 🤣🤣. Yes I guess the rush for car charging and battery storage does make it more versatile... ...
Sounds like I will have to look into this. We have a Solar wet system plumbed into the second heat exchanger of our DHW tank (you may have seen the ri...
Latest Posts
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RE: Advice on Vaillant Sensocomfort
@jamespa Thanks, that’s useful. It also seems the ...
By Batpred , 1 hour ago
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RE: Debugging my legionella immersion heater
I notice this (66 is rather hot) with my legionella cyc...
By JamesPa , 7 hours ago
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RE: DIY Heat Pump Installations: Navigating Legal and Regulatory Hurdles
@transparent I thought you would spot that wind turbine...
By Batpred , 7 hours ago
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UK warm homes plan - how can it be delivered?
@editor Sobering thoughts on your article on the workfo...
By Batpred , 9 hours ago
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RE: Setback savings - fact or fiction?
You are right to be intrigued by it IMHO. SOFAIK it is...
By JamesPa , 15 hours ago
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RE: Octopus Cosy Heat Pump Owners & Discussion Thread
@swwils there is no logic to oversizing a heat pump. It...
By AgentGeorge , 18 hours ago
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RE: Vaillant Sensocomfort Time
Thank youy for the pointer. I think I have managed to ...
By ispookie666 , 1 day ago
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RE: Forum updates, announcements & issues
I have been doing a lot of work on the site lately and ...
By Mars , 1 day ago
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@majordennisbloodnok good advice, thanks for that.
By David999 , 2 days ago
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RE: My Grant R290 9kW Heat Pump Installation
I am following this thread with great interest and than...
By TaffontheTaff , 2 days ago
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RE: Sizing an ASHP; Heat loss and kW
You can't measure heat loss with a website. But you ca...
By JamesPa , 2 days ago
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RE: Estimating true heat loss from twelve months of consumption data
@ian33a — I have a sort of residual interest in this pr...
By cathodeRay , 2 days ago
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Hi, Thank you. So its a Daikin Altherma 3M...
By Lbart68 , 2 days ago
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I have a Contactum CU. Would the below RCBO (descriptio...
By Batpred , 2 days ago
