marshian

I need another hobby

When I re-do my downstairs circuit I'm still going to "reverse return" the flow and returns from all the rads ie FIrst Rad "flow" is last Rad "return" etc

Coming back to this - I don't think it needs a floor plan type arrangement - I was think more a "Is room above heated Yes/No" Target temp = "X" Then the dt function for internal differences takes this into account?

So the quote is £13,700 before the BUS Grant Contribution and for that they are going to Install an ASHP and link into existing pipework commision and set up There is no Rad or HW Tank upgrade or UFH involved? I think I'd be getting several other quotes or considering replacing the gas/oil boiler for another!!!

Are you trying to stay inside the BUS grant so effectively a “free to you” change to ASHP? if no rad/cyl changes then where is the £7500 going?

Thanks Probably a good time to provide a review In summary - I found the "Open Heat Loss" tool easy to use (The dt element between rooms/external areas probably needs a bit more notation to explain what it's trying to achieve from a "non heating engineer" perspective - clearly you had an excellent understanding of it and could fix my schoolboy errors) I completed the whole house heat loss over two evenings - maybe 2 hrs each day I did however have 1. All the dimensions of floors, walls, windows and doors in a handy table 2. All the U values for the fabric elements of the house noted down Both the above from a previous heat loss exercise which made data entry quite quick and easy It works on phone (if a little scrolly) Android tablet and PC The various report pdfs are great as a summary snapshot I need to go back to my pipe work section and revisit that as I took a punt on lengths I effectively have two circuits linked together just after the pump If I was to suggest anything it would be - from a room to dT perspective it would be good to link ground floor to upstairs (In my mind I have a "room above" or "room below" selection process) how feasible that would be I don't know

OK that makes sense - I considered removing all the doors from the landing the whole landing, hallway stairwell area is also a bit tricky I broke it into chunks to make it easy for me as they are all linked but only one radiator (albeit a big one) is in the lower hallway (so the tool says it's oversized) however if I add all the reqts together it's in line with the other rooms It used to be a 550 by 800 T11 - it's now a 500 x 1400 T22 Makes perfect sense - before I insulated between the joists of the ground floor with 75mm PIR you could feel a draft in most rooms when the wind got up - now it can be a bloody good gale outside and there is no drafts at all........ I know I've got the house reasonably well sealed hence the installation of a PIV unit to manage humidity and ACH's (But it's not MVHR )

Last point - pretty sure it's ventilation losses that are driving the higher calculated heat loss Fabric is now 4144 W Ventilation is 3090 W Anyway to reduce that ventilation factor? I guess I see a blower test in my future

OK checked out the changes - made a couple of tweaks now I understand the logic More stupid questions 6 rooms upstairs all have doors then I treated the landing as a room and put 6 doors in there.......... Ceiling for all upstairs rooms is plasterboard & then 300mm Insulation and over boarded - temp in the loft is always 2 to 3 deg above OAT should I be lowering the delta from room to ceiling Same with the temp below the suspended ground floor it's always higher than OAT

Bloody amazing Simon - thank you I'll go in and check out where you've made the changes

Amusingly for me anyway the total actual Rad output is spot on for my heat loss I know I've cocked up somewhere just can't see where 🙂

Sent you a PM

Rad Evaluation at my Target Flow Temps

heat rises easier than it falls??

So now I need to understand why the result (if I am reading it right) at 12 kWh is 3 times my current heat loss 🙂 Current heat loss is just under 4.0 kWh at -2.5 Deg C So I've definately made an error somewhere