ASHP & triple glazing

[Joeboy]

Recycled Kilims look great Joe.

See a side hustle developing there

Could be the case btb, I clicked with Ibrahim, got a bit of gen on his travels for rugs, family etc. I particularly liked as did swmbo that he spoke of laying out and numbering the klim squares during overlocking so that when they went to the village for handsewing he got the end result he looked for in the design.

I can't verify this but be he said the kims are 80 to 100 year old before they get beyond it and can't be repaired. They literally go for rags at that point. Some of the old rugs he showed us today were mindblowing.

I'll post photos of what we bought once back tomorrow. Just left Goreme on the bus. Same driver as brought us out!

[Bugtownboy]

Love Middle Eastern/Asian rugs.

We have several, different sizes and, obviously design, from Turkey through to Tajikistan.

If you could support a ‘recycling’ industry.

Wow !

[Joeboy]

Love Middle Eastern/Asian rugs.

We have several, different sizes and, obviously design, from Turkey through to Tajikistan.

If you could support a ‘recycling’ industry.

Wow !

I was light in my bartering, well aware I'm helping support essentially a cottage industry.

He did say that Turkish carpet making is dieing out. The majority of handknotted rugs now come from Iran. I didn't know that. Back home now, the bustrip was quick.

A few night photos before bus.

[Joeboy]

Rug & runner are out. I forgot what depth a rug adds. Pops colour & texture into the mix and glorious to walk.on. The bedroom rug ended up.in the lounge and the hall runner ended up in the bedroom. I'll be in touch with Ibrahim again.

Tomorrow swmbo.wants to revamp the library in the lounge. So we're playing wee hooses. A bit colder tonight so I have set the a2a HP in our bedroom to heat.

[Joeboy]

When I worked away and we used to taunt ourselves with when we were getting home. You don't count the day you are in and you don't count the day you.travel as that's a 'get up and go".

I am awake for the first call to prayer and realised it's 10 days and a get up and go for the ashp install starting. SWMBO has already let daughterly know she's coming to Edinburgh.place for a few days.

I'll load up on T & biscuits and hope that helps keep the job quality high.

I really shouldn't be this excited for a home heating upgrade?

[Joeboy]

Lovely, downstairs A2AHP putting out the merest of puffs of air to maintain 23 degs. Watching the Tyson/Paul documentary. I'm calling Tyson to win by KO in the second round with an uppercut or right X. The boy Paul is flatfooted and doesn't ground his punch through his hips or opposite foot. Tyson might be 58 but if he doesn't run out of steam in the 2 minute rounds....



Edit, We go to bed early here and sleep like children. Lovely to come upstairs and switch on this floors new A2AHP.

SWMBO was surprised as it actually spooled up a little rather than flutter feeding warm air. Still not the solution for our Scottish home but very impressive for this scenario.

[Joeboy]

SH are great in many ways:

• Shift usage into cheap period powered by Octopus’ generous ToU tariffs.

• Multi-decade reliability with zero maintenance.

• 100% efficient.

They are a really great part of the puzzle when transitioning form burning FF locally to an all-electric house while maximising offpeak:peak ratio.

However once you’ve achieved the above, the next step is to reduce the amount of off-peak electric you consume, and a HP is a really great way to do that. The 300-400% efficiency and low/slow power usage means that a HP plays nicely with a battery/inverter too.

Once I'm up & running I'll see if we can set up a curve that benefits the overnight slots by a degree in temp on the ashp. Defo running a TRV on our bedroom rad. The rest we will let equalise. I'm interested in seeing what the ashp will modulate down to?

HPs generally modulate down to 25% of their nameplate capacity. The stories you read in the press with people finding their HP expensive to run tend to be: oversized units cycling on and off frequently because they’re unable to modulate down low enough, and people using them like a gas boiler switching on-and-off several times a day.

It seems to me that it is best to fit an undersized HP and rely on secondary heating (log burner, resistive electric, etc.) on the very coldest days.

Hope you don't mind Stinsy, I quoted you to this thread?

The heat calc for the house comes out at 7.94kW with an.outdoor temp of minus 4.74degs. This is based on the lowest Uw value possible in the heat cal software which is 1.0. Our windows of which there are 26 sqmtrs have a Uw of 0.7...

The HP specified is a 7kW unit.

The heat calc has us down for these consumption figures 5,471kWh consumed for home heating.
(17,124kWh generated SCOP 4.13)

1,396kWh consumed for dhw.
(5,094 kWh generated SCOP 3.65)

All above combined is 29,085kWh generated for 6,867kWh consumed, a theoretical combined SCOP.of 4.12.

For posterity, using Nov & Dec 23 home use figures to complete the 2024 year we would be 19,000kWh bought from the grid across the complete year.

Going out on a limb of guesstimate I can say 4,000kWh on EV charging, 120 days full home stack charge, call it 5,000kWh. That leaves 10,000kWh for home & dhw heating on a 1:1 basis in 2024.

Going on the projected SCOP. and consumption figures we can hope to drop the annual use incl EV and stack charging to 14,000kWh.

Hoping that the current battery pack(s) will have the legs to run the whole show at 7p per kWh we would be £480 for the year heating & DHW. Considering we generate about 8,000kWh at home and can bank a lot of that to the VB any imbalance in consumption through season will be nulled out.

These figures will improve I think due to the improved spec of the to be installed 3g and we intend to fully embrace the concept of low & slow as SWMBO has said she still wants the WBS on in the evening (fair enough). It will be interesting to see how these two pieces of technology, one ancient and one new work together?

I've still to get my head around the fact that dhw is going to be supplied on a multiplier.and that our faithful solar boost will no longer be required!

So the power that used to go straight to hwt 7 months of the year will now be sold to the grid in whichever export contract presents. Anyone looking for an inexpensive solar water heater fitted with a robotic app controlled demand finger(switchbot)?

On the opposite side so to speak our 40kWh battery stack won't be exporting much to the grid in Wintertime as its going to be needed to run the ASHP. If it does modulate down to 25% of its capacity that's 1.75kW of power demand of which I can expect 500W from the PV even in Winter generation conditions. That power draw on the 3.6kW hybrid inverter points me firmly at a 5kW hybrid inverter come the day. The current unit is 6 years old, I think they last about 10 years?

I'm pretty sure I asked Iain what he sees in load when his 9kW unit is running low & slow but I can't remember the answer and photos aren't showing up for me.

Anyway I hope these wittering are of some use. They certainly help focus my mind.

P.S, guys on here showing 500W load when running low. Not sure what size of unit they are running. Our big A2AHP out here runs as low as 400W. I have hopes!

https://community.openenergymonitor.org ... read/21891

P.P.S That fella has a 5kW unit and the floor is 450W for him.

[Stinsy]

Once I'm up & running I'll see if we can set up a curve that benefits the overnight slots by a degree in temp on the ashp. Defo running a TRV on our bedroom rad. The rest we will let equalise. I'm interested in seeing what the ashp will modulate down to?

HPs generally modulate down to 25% of their nameplate capacity. The stories you read in the press with people finding their HP expensive to run tend to be: oversized units cycling on and off frequently because they’re unable to modulate down low enough, and people using them like a gas boiler switching on-and-off several times a day.

It seems to me that it is best to fit an undersized HP and rely on secondary heating (log burner, resistive electric, etc.) on the very coldest days.

Hope you don't mind Stinsy, I quoted you to this thread?

The heat calc for the house comes out at 7.94kW with an.outdoor temp of minus 4.74degs. This is based on the lowest Uw value possible in the heat cal software which is 1.0. Our windows of which there are 26 sqmtrs have a Uw of 0.7...

The HP specified is a 7kW unit.

The heat calc has us down for these consumption figures 5,471kWh consumed for home heating.
(17,124kWh generated SCOP 4.13)

1,396kWh consumed for dhw.
(5,094 kWh generated SCOP 3.65)

All above combined is 29,085kWh generated for 6,867kWh consumed, a theoretical combined SCOP.of 4.12.

Hoping that the current battery pack(s) will have the legs to run the whole show at 7p per kWh we would be £480 for the year heating & DHW. Considering we generate about 8,000kWh at home and can bank a lot of that to the VB any imbalance in consumption through season will be nulled out.

These figures will improve I think due to the improved spec of the to be installed 3g and we intend to fully embrace the concept of low & slow as SWMBO has said she still wants the WBS on in the evening (fair enough). It will be interesting to see how these two pieces of technology, one ancient and one new work together?

I've still to get my head around the fact that dhw is going to be supplied on a multiplier.and that our faithful solar boost will no longer be required!

So the power that used to go straight to hwt 7 months of the year will now be sold to the grid in whichever export contract presents. Anyone looking for an inexpensive solar water heater fitted with a robotic app controlled demand finger(switchbot)?

On the opposite side so to speak our 40kWh battery stack won't be exporting much to the grid in Wintertime as its going to be needed to run the ASHP. If it does modulate down to 25% of its capacity that's 1.75kW of power demand of which I can expect 500W from the PV even in Winter generation conditions. That power draw on the 3.6kW hybrid inverter points me firmly at a 5kW hybrid inverter come the day. The current unit is 6 years old, I think they last about 10 years?

I'm pretty sure I asked Iain what he sees in load when his 9kW unit is running low & slow but I can't remember the answer and photos aren't showing up for me.

Anyway I hope these wittering are of some use. They certainly help focus my mind.

P.S, guys on here showing 500W load when running low. Not sure what size of unit they are running. Our big A2AHP out here runs as low as 400W. I have hopes!

https://community.openenergymonitor.org ... read/21891

P.P.S That fella has a 5kW unit and the floor is 450W for him.

I don’t have much to add other than I agree with all of that. In the world of gas boilers the received logic is: “bigger is better” and “no one complains their house is too warm”. A plumber with decades of experience with gas might therefore see your 7.94kW calculated demand and fit an “11kW” HP which would be a mistake.

If I were you my strategy for the shoulder months would be: HP off, burn one small-medium log in the evening to provide a bit of cosyness. When you feel the there is enough heat required that the HP will run at its lowest setting (maybe 1.75kW (?)) without cycling, fire the beast up and let it run low-and-slow for the duration. The critical settings are: as low a flow temp as can get rid of the heat given your emitter sizing, and your weather compensation to increase that flow temp in reaction to lower outdoor temps. This might be something you need to fiddle with.

The received wisdom is: most people need a 3.6kW inverter unless they have a HP in which case they need a 5kW. If you want to avoid peak electric on the coldest days when the HP is cranking at full whack then 3.6kW is going to be tough (I manage with 3.6kW inverter and 7kW HP but I’ve been looking at 5kW inverters on eBay…). You could possibly benefit from a 5kW in any case to help with SS, PowerHours, and the like. The price difference between what you’d get selling your old one and buying a new is pretty small. You need to think about I’d the DNO are busy people with enough to worry about..,

Those DHW solar diverters have been paperweights ever since Octopus started paying us 15p for export…

[HML]

On the opposite side so to speak our 40kWh battery stack won't be exporting much to the grid in Wintertime as its going to be needed to run the ASHP. If it does modulate down to 25% of its capacity that's 1.75kW of power demand of which I can expect 500W from the PV even in Winter generation conditions. That power draw on the 3.6kW hybrid inverter points me firmly at a 5kW hybrid inverter come the day. The current unit is 6 years old, I think they last about 10 years?

If you think you're going to get much useful PV energy in winter you are going to be disappointed. For a start days are short, if you're lucky you might get 4 hours of daylight in the depths of winter, but that daylight isn't going to have much useful energy. If it's cloudy you can expect no useful PV energy.

We have about 18kW of panels, albeit not very well aligned. Over the last 11 days they have averaged 3.1kWh per day. That's not enough to cover the losses in the charge/discharge cycle. And it's not even the depths of winter yet. Just before the cloud set in it generated 31kWh on one day.
(The sun's just come out after nearly a fortnight, so we're getting 5kW!)

Our ASHP is nominally 8kW. The maximum electrical draw is just under 3kW, minimum is just under 400W. Once the system has stabilised it will run at the lower rate for some time, but it stills runs at maximum output while heating hot water or starting a heating period, so maybe 3 hours a day at full bore at the moment, with 7C outside temperature. Just an example as this stuff is very installation dependent.

[Joeboy]

The wbs will continue to play a role. There will be tweaking I'm sure. We spoke this morning and the defining temperature for the house will be the temperature that swmbo wants the ensuite bathroom to be at for her morning shower.

Basically going to use the ashp to maintain the low temp we want to live in. I see 20 degs bandied about but that's too high for us with the WBS in play. I reckon more like 18.5 degs and the whole home is the thermal mass at that temp.

Who knows though, I'm sure I have a lot to learn.