marshian

Nice work I'd better add a bit more info We have a PIV unit installed - takes air from the loft and pushes it into the house - it's not MVHR but it solved the issue when I insulated under the ground floor and humidity levels spiked due to the reduction in drafts. It cuts off at anything above 25 deg in the loft (so summer during the daytime it's mostly off) It does a fairly good job run (08:30 to 15:00 provided the loft temps don't turn it off early) and 00:00 to 06:00 overnight when we are the main drivers for humidity (Sleeping) I've never calibrated the Humidity and Temp Sensors but from a temp perspective they are pretty damn close to other devices reporting temps so I'm comfortable with trusting the info What I would say is that all my humidity readings I feel are on the high side and I'd like them to be lower but when we ventilate the house on good dry and sunny days the readings go a lot lower into the low 40's (much lower than the loft!!!) Last thing the room with the sensor is heated in winter but on a set back temp to the rest of the house as it's north facing - has three external walls and loses a shit load of temp very easily (last winter it also had a large area off loft insulation missing) - If I'm in that room working on my PC it heats up quite quickly

As I said earlier I've been logging for a while My External Sensor (Tempo and Humidity) is actually in a well ventilated loft My Internal Sensor (Temp and Humidity is in one of the bedroom) Hopefully this table will work OK Month Avg External Temp Avg External Humidity Avg Internal Temp Avg Internal Humidity Aug-23 20 62% 23 60% Sep-23 20 68% 22 64% Oct-23 15 80% 19 67% Nov-23 9 89% 13 73% Dec-23 10 91% 15 69% Jan-24 8 86% 14 64% Feb-24 11 86% 15 67% Mar-24 12 79% 16 66% Apr-24 13 70% 17 63% May-24 18 66% 20 65% Jun-24 19 58% 21 59% Jul-24 20 61% 23 59% Aug-24 21 57% 24 56% Sep-24 18 70% 21 64% Interested in Mike's xls sheet I plugged this years data into it

I know it's an old thread - but I got a very good measurement of my heating circuit by reading the water meter before a refill after a drain down (I subtracted the volume of the header tank

Not wanting to take this thread off topic perhaps I should start new thread 😉 It's 5.4 Litres of hand built V8 - made a bit nuttier by AMG - then thrown in a car with a short wheelbase and not enough room in the arches for a more suitable width rubber so anything more than a moderate throttle lights the tyres up. 🤣

Luckily we have a fairly good one at my workplace and I've got permission to borrow it this winter - seems a bit pointless to look at much at this time of year - you really want to use one when the house is up to temp and it's cold outside to show the biggest leakages (IMO - happy to be shown to be wrong)

Amen Brother Stupid V8 in a silly car = Lots of fun

Pleasantly surprised lots of normal GD "stuff" was missing Zara didn't get pregnant You didn't got over budget but came under (OK not quite finished but close enough) The house was "finished" before target time The garden wasn't finished but the bones are there. I amazed GD didn't can the programme due to not enough drama 😉 I guess the look of the house and the corten provided that...... Well done

You are taking what I said out of context - yesterday "specifically" the boiler wouldn't work (so WC wouldn't work too) with all the TRV heads removed (I tried that in case it was a flow issue)

I was intending if it all works as it should to just use the decorators caps - she turns those it turns the rad off

WC comp wouldn’t work with all the TRV heads removed 😉 It was heating water to weather comp 37 deg Seriously it’s not a Wiser issue the boiler doesn’t know whats going on outside it’s flow and return temp and the volume of water passing thro it - sure TRV’s of any type (smart or dumb) can influence all of those things but so can balancing and pump speeds There is no link between Wiser and the boiler other than a call for heat (either for HW or CH and currently the boiler doesn’t even know that as the HW demand box has been disabled as well as WC) I’m sure it’ll get resolved fairly quickly because I’m not paying the bloody bill until it is 🙂

And it is something I will seriously consider (save me a few quid in batteries every year and stops SWIMBO winding up the TRV’s cos the radiator isn’t hot enough)

Do people not read posts WC is turned off because it’s not working when it is I may well ditch Wiser altogether 😉

This is why I think I need to give the boiler control of the pump It happens so frequently the last message from the vicare app was That’s definately Wiser buggering around trying to save a bit of gas If I give the boiler control of the pump it won’t be able to stop it - as a result it’s regular attempts at saving gas will be thwarted I might have to go back and tell Wiser it’s an Oil Boiler not a gas boiler again - that helped a lot with the old boiler but I’d told it it was a gas boiler again when I had the new boiler installed (clean slate and all that)

I’ve set the TRV setback at night to 10 deg lower than day time setting to stop that issue happening at night - day time I’m hoping that weather comp and the correct flow rates thro each rad stops that happening. Last year I stopped Wiser intervening on the approach to target room temps by having one TRV set to 5 deg higher than target room temp and not having it on the rad (std non smart TRV was on the rad) that and a pump overun stopped the Wiser from shutting down the heating and leaving the boiler hot and kettling

Oh I tried the switch it off and on again trick….. Boiler now reset to dumb boiler - no weather comp (well I’m doing manual weather comp based on what I think the house needs) and it’s heating water and running CH fine Waiting on Viessmann technical before we try this WC and HW demand thing again Tomorrow the job will be running a cable from pump back to the boiler so boiler has control of the pump - should stop the 75 errors I’m getting when Wiser decides to pause the heating. Floor is up in places already so might as well do that Quite tempted to run another run of 22mm copper to split the flow and returns (currently they are slapped together in the same notched joist) then I can insulate the pipes individually we shall see how today goes (roofing the shed with EPDM has priority before the weather turns to shit)

One manual on the bypass rad all the rest are wiser

And today I has nothing……, CH - all rads call for heat, pump fires up and water circulating at 1.1 m3/hr - boiler does nothing HW - (CH zone closes HW zone valve opens), tank stat is calling for heat, water is circulating at 1.2 m3/hr - boiler does nothing cool beans!!!!!

Ok so I downloaded the vicare app at this point I wasn’t looking for a solution I wanted to understand what was going on So there you are the weather comp curve in the app WTF is going on!!!!! Lets see if I can change that That’ll do for now hit save and boiler does a massive stall and modulates down to 3/5th’s of (expletive deleted) all and temps start falling fast It actually then cut out and 20 mins later fired up at a nice 37 deg C and 10.6 % modulation (which I cannot work out as kWh because it makes no sense at all)

So Friday progress - some good, some not so good but might be normal - who knows??? System drained down (so we could swap out the zone valve) HW demand box fitted and wired into the boiler - that required lifting some floors again as well as feeding it alongside the flow and return pipes from boiler to HW tank. Wifi module fitted - getting that to work involved a bunch of calls to Viessmann technical help NC Zone valve for CH swapped out for the NO zone valve System refilled - christ I hate how bad this system is from a drain down - my last resort is often putting a hose on one of the drain points and sticking mains pressure up the pipe...... Massive air lock again - every bloody time this system is a cow to re-fill) eventually opening the lowest point drain valves for both flow and return as well as the boiler drain valve o they flowed resulted in a shit load of spluttering followed by a decent flow and then all the rads filled and bleed out nicely Boiler then re-set up with weather compensation (wasn't done last time because I didn't want weather compensated HW heating) we set the slope to 1.4 (which is the default) I actually think 1.2 will work but lets be on the high side we can always decrease or increase if my guess is wrong............ So time to fire it up and that's where the fun started Needed some HW for bath night HW selected boiler fires up 60 deg flow temp set point - well that's a bit crap can we ramp it up a bit - bath night I normally run the boiler at 70 deg flow to get the tank to 60 deg. No matter what we tried the 60 deg was the max............... so HW demand box ignores the weather comp but caps the flow temp to 60 deg C 45 mins later I had a tank of 50 deg water and I took the attitude that that'll bloody do if she wants a hot bath she'll have to drain the damn tank Lets do CH Boiler capped at 37 deg C - I can lower it but not increase it - it's maybe 12-13 outside so that kinda lines up with the slope (ish) Lets give it a go So what I expected - boiler would fire up drive up at a fairly soft rate initially - it would monitor the flow and return and with a stone cold system wind up the burner to match the flow and get up to target temp fairly quickly It did just that but over shot 37 deg - that's OK I thought it often exceeds the flow temp by up to 6 deg to keep running rather than cycle (neat trick that unless you have flow and return temp monitoring you'd never bloody know but I have just that set up so no concerns here) At an actual 56 deg flow temp I had concerns!!!! I'll do what I did next in another post because I need some screenshots from my phone and they aren't on this PC so just imagine the Eastenders theme tune is banging away as this post ends

You were doing so well until the last section ^

Collected the I-Joists tonight - they've been dry stored for a while it seems but are new and never used Need to have a google and see how best to join them end to end 1. minimise cutting losses 2. provide addition strength where the join isn't above a roof truss I was thinking OSB sandwich plates either side of a join and either screw thro or bolts?? Before anyone goes a bit nuts bear in mind they are being joined over a max span of 600mm - it's not like they are being joined to create a larger span - that would be a bit daft

So to continue on a more positive note After the boiler was fitted I explained to the gas engineer that I wasn't exactly a happy customer but as he had done everything he said in the quote I would settle the balance however I would like him to supply what I asked from an operating perspective I sent him 1. links to various X-Plan set ups (Both web sites and youtube videos) 2. Details of Viessmann part number 7574319 cunningly titled "Cylinder demand terminal box" 3. Links to suppliers of NO zone valves 4. Kimbo write up of why DHWP should be used I was being helpful although I would have expected someone who was asked for DHWP and specifically a combination of NC and NO zone valves to maybe say - actually fella you're speaking a different language to me - can you help me understand it....... Anyway this Friday he's coming back with a NO Zone valve, Cyl demand box and the wifi module which has been on back order since the boiler was fitted and hopefully we can keep the smoke in the wires. Because in my original brief I did put "The boiler change is not to save gas – it’s to stop me having to constantly manually adjust the flow temps based on expected weather and having to heat water at elevated flow temps manually. I’ve got other hobbies I’d rather concentrate on."

I did and apart from the engineer I used the nearest alternative Viessmann installer was 55 miles away and he wasn't interested in travelling for the job and as a result quoting for it either...... Problem with living in East Anglia I guess. The £3600 was including all materials on the quote below Drain down current heating system and remove boiler from kitchen Supply and install a Viessmann 100w 16kw heat only boiler Supply and install a weather compensation sensor on north facing wall Supply and install the WI-FI module to boiler Supply and install a new flue with plume management kit Connect gas pipe and adjust as needed Connect condensate and adjust a needed Convert the heating and hot water system to a S plan with a normally open zone valve and a normally closed zone valve giving hot water priority Commission boiler Register with Viessmann for a 10 year warranty Register with Gas Safe Five days prior to start date we would need to add a system cleaner to the current system so we can chemical flush it in the day of the install A 50% deposit is required before the start date with remainder on completion That should have rung alarm bells with me What I got was a weather compensated boiler in an std S plan set up with NC zone valves on both HW and CH It also doesn't know if it's doing HW or CH so weather compensation is pretty bloody useless unless I want to heat water at 35 deg flow temp I was just a little bit piddled off on the day when he finished the install and said so how do I set the temp for water to be different for CH and he said you just set the flow temp to 55 Deg..................

I'm not going to reply to all your very good points in turn for a couple of rreasons I'm kinda going back to April this year when I was decided on what I wanted and will move shortly to July when it was installed............... It modulates down to 3.1 kWh and my intention is very much to "zone less" once the "issues" with the install are resolved....... This will be My Viessmann boiler journey "part II"

Background Current house owned 33 years but updated over the years early 1980's built detached 4 bed so originally 1. Open cavity walls. 2. 25mm of loose fill loft insulation. 3. Single glazed doors and windows. 4. Suspended floor downstairs over a 2 - 3 ft crawl space. 5. Heat only boiler (non condensing). 6. T11 rads in some cases sized a little on the mean side. Back in 1991 we had an annual gas usage for CH and HW of 25,000 kWh It’s two floors with a total floor area of 113 m2 (Small extension done in 2006 to building regs at the time) have reduced energy consumption over the years with Double Gazing, Cavity wall insulation, upgraded loft insulation (75mm so could still be better), new condensing boiler got us down to 16,500 kWh per year Most recently every rad in the house has been replaced basically changing T11’s for T22’s of similar or larger size and a few verticals where space for T22’s was a challenge or SWIMBO demanded something “more modern” I also spent 3 months in 2022 doing 56m2 of 75mm PIR between the joists under the ground floor. The PIR was an amazing reduction to heat loss considering heat is supposed to rise but the airflow under the house is quite a high rate when the wind blows with one air brick every five bricks outside (house was built near a flood plain and the water table is quite high) The other contributor may or may not be fitting Wiser controls and Smart TRV's but last winter I ran it like an on/off timer rather than a 24/7 with setbacks due to issues I had with heating controls (old sunvic wiring centre with relays) I was running a manual weather compensation for CH and turning the flow temp up to do HW The last few improvements got us down to 8500 kWh gas usage per year for CH and HW but the current boiler for last 14 years was driving me nuts. It was a Glow Worm Flexicom 24HX (So 10 kW min) and it cycles like crazy. When I did the heat loss calcs it confirmed to me that we had a heat loss of 4,500 kWh at -2 so clearly there was a good reason why it cycles. Annoyingly I replaced the vented HW tank a few years ago (old one needed 1 hr to heat water due to scale inside - hard water area) so it's not that old but I'm sure you are right if I could get a better vented HW tank with a high surface area coil it would probably help a lot when at lower flow temps (at the same time I fitted a water softener so I'm not expecting the same level of scale build up impacting water heating performance) So with the boiler driving me crazy and wanting to bring forward potential big spends to before I pack up work I wanted to buy the right boiler this time. So I did a lot of looking at boilers before deciding on a Viessmann 100W “Heat Only” I wrote a short brief of the “Proposed System” Boiler Required: Viessmann Vitodens 100-W B1GA 16 kW Location same place as existing Glow-Worm Flexicom 24HX Flue needs to be supplied and fitted with a plume management kit (vertical after exit thro wall as a car port is next project) External wired weather compensation sensor Wifi Link Board (So I can link to Home Assistant). Convert to DHWP with CH being the rest position (normally open) on a 3 port (2 position valve) or two zone valves NO for CH and NC for HW Set up to weather comp for CH flow temps (38 to 50 so slope of 1.4 as a start point but I think it will end up at 1.2) and full boiler output at 80 for HW requirements Considering HW cyl replacement with larger coil for lower flow temp water heating but may do this at a later stage as the efficiency gains from heating HW at lower flow temps in summer are quite small. I asked a few local gas engineers to quote but most either weren’t Viessmann trained (so no chance of the 10 year warranty) or wanted me to accept a different boiler (WTF is that all about) Anyway one gas engineer was Viessmann trained and said he could do what I wanted and came back with a quote of £3600....... (ouch) I gave it some thought........ A lot of thought....... £3600 buys a lot of gas!!!!! (About 72,000 kWh at current prices so I could cover the heating needs of my house for 8.5 years.........)