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So plumbers have sent over adjusted calcs………
This puts all rooms basically bar my office, the main bathroom and downstairs toilet at watt deficits with current rads even at delta 20 (which might explain a lot!).
I've looked at delta 20, the MCS correction factor of 0.2325 (think that's basically 16.5 as Derek pointed out).
Doubling the eskimo heights should fix downstairs (including doubling the width of the hall rad), but MCS calc would still put the Living 2 down by 400W if ignored Eskimo's correction factor. I'll have to have a think about that, I suspect the Eskimos are actually quite good, but they've got such a deficit atm due to poor calcs in first place. For context Living 2 is down by 382W if delta 210 atm, 1286W at delta 16 and 2520W using MCS factor.
Upstairs is down other than my office as per above (explains why it's 21C in here quite easily). The deficits at delta 20 look around 300-370W between bedrooms, going up to 920W using the MCS factor (Basically 4.3x oversize).
They could be fixed with K2 up sizing, but the landing would suffer still according to the calcs.
I wonder if upstairs would just get away with it with the heat rising.
Problem I have is it's hard to judge the system as it is in mild weather etc.
@crimson With our system being commissioned on 19th. February last year - with a very mild spell for some days, I had to approximate the balancing work until the winter arrived. November of last year cooled down so I commenced the rounds of tweaking and all is well now. (I even query over 0.5 degrees C. between rooms now!) This difference is nearly always due to solar gain on the south side of the house and the ‘node’ that senses being in the living room that faces north east. Regards, Toodles.
Toodles, heats his home with cold draughts and cooks food with magnets.
Posted by: @toodles@crimson With our system being commissioned on 19th. February last year - with a very mild spell for some days, I had to approximate the balancing work until the winter arrived. November of last year cooled down so I commenced the rounds of tweaking and all is well now. (I even query over 0.5 degrees C. between rooms now!) This difference is nearly always due to solar gain on the south side of the house and the ‘node’ that senses being in the living room that faces north east. Regards, Toodles.
Thanks Toodles, hopefully I can get there.
Does look like a lot of rad changes incoming however due to a complete mess up by the plumbers but will see. Glad that calcs show even using delta 20 everything is off. I didn't things were so badly off, but maybe explains why the ASHP cycles like crazy.
4 days later, with guests over the weekend I left things mostly alone. I did end up changing the secondary pump speed to 1/3 as lock shields became a bit noisy in the living room. Temps seemed to have stabilised around 19.5-20C downstairs. 20.5C upstairs mostly (with lockshields right down). TRVs essential upstairs as rooms get too warm (19.5C is ideal really) unless windows open a crack. What's clear is the office is the most performant room and that I guess reflects the updated calcs that imply it's the only correctly sized one currently rad-wise.
I'm still awaiting confirmation when radiators will be swapped out. I'll have a bit of time next week to try the method of using a heater timed off and on to broadly see how many watts down we are.
All looks a bit of a mess, where's the lagging.
I was working on a Grant this week and I’m ripping out all those valves, extra pumps and low loss header.
Installing a new 3 port making the system open loop.
Posted by: @kenboneAll looks a bit of a mess, where's the lagging.
I was working on a Grant this week and I’m ripping out all those valves, extra pumps and low loss header.
Installing a new 3 port making the system open loop.
Hi Ken, lagging is done just used an old photo for the detail of pipes. I’m hoping for rad upsize replacement then will look later in the year for removal of unnecessary parts. What areas do you work in?
that’s ideally what I’d like to have done to (once current plumbers sort the rad sizing under the contract, I don’t want them touching anything else). Its clear temps drop across the plant room alone across all this mess. Hopefully I can find someone locally to do this later in the year ahead of next winter!
@kenbone bloody hell. That would have freed up a lot space in the utility/plant room 😂
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Posted by: @editorbloody hell. That would have freed up a lot space in the utility/plant room 😂
probably about a grand's worth as well. which could have been not spend during the original install.
its not just for laughs that we keep banging on about single loop....simpler, cheaper, more efficient
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210m2 house, Samsung 16kw Gen6 ASHP Self installed: Single circulation loop , PWM modulating pump.
My public ASHP stats: https://heatpumpmonitor.org/system/view?id=45
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