Marvin

Roof pitch? Roof Azimuth?

Hi. My gut feeling is that the CH temp is too high, but I'm sure someone will correct me. It seems to heat up very quickly and the shut down then heat up very quickly and shut down... Me, I would have it at 55C and see the difference....

Hi @Wil To clarify our position we have good AIM and APE. That is Airtightness, Insulation, Mechanical Ventilation with Heat Recovery, and Air Source Heat Pump, Photovoltaics and Electric Vehicle. We have 5.12kW of panels on a south facing roof with no shading, but also we live in the south of the Isle of Wight so we have about 400 hours more sun a year than the East Midlands. For our 104m2 well renovated bungalow with Airtightness, Insulation, Mechanical Ventilation with Heat Recovery we're now using about 1650kWh to heat the building for a year. We installed and are testing our off grid battery system during this winter but expect to use it almost every day in the summer. We only have 1 rate of electricity. Our PV produces 1/4 of the output in the winter compared to the summer. Compared with us I think your HP's are sucking all the available power up. This may be of interest: Aim to go APE It worth considering all the AIM and APE elements before making decisions. That is Airtightness, Insulation, Mechanical Ventilation with Heat Recovery OR Heat pump Ventilation, and Air Source Heat Pump, Photovoltaics and Electric Vehicle. Some of these will not work properly without the others, and some will complement others: A MVHR will not work properly without Airtightness. An Air Source Heat Pump will have to compensate for the lack of Airtightness and/or Insulation to the degree that the benefits become questionable, especially during winter, without them. An ASHP uses electricity and Photovoltaics can supply a little during winter and a lot during summer when cooling can be a problem and an ASHP can supply cooling. PV can supply a little to an Electric Vehicle during winter and plenty during summer if your vehicle is at home during sunny days. Extending a property and only doing AIM works to the extension will be no good, you have to do all the property within the thermal envelope. And thinking of running costs: a) Airtightness and Insulation should have no running costs and last (Well, loft insulation lasts over 40 years, in our experience) with the exception of UPVC units for windows and doors, but that being said it will last 30 years? b) Our MVHR unit servicing 100m2 floor sized home uses about 260kWh a year; far far less than would be used to heat incoming cold fresh air in winter, and we clean the filters twice a year. c) ASHPs are, in my opinion, still in their infancy but we are now in the second year of use here. We were very careful to follow best practice in the design and installation of our system, did a lot of bespoke tweaking, and we now have an upgraded 1970’s timber framed bungalow that uses less than 20kWh per year per m2 of floor for heating. d) PV would be a lot less attractive if there is no ASHP or EV (or battery backup) or diverter to the hot water immersion. In my humble opinion, if you have a suitable roof you should install as much a physically possible. Electricity production costs (cost per kWh) are difficult to evaluate because it depends how much is used and how much is supplied to the grid. We decided to go with the PV cost divided by 7 years, which for us works out at £1.60ish per day. Yesterday the PV produced 12kWh all of which we used. Remember, 5kW of PV panels will not produce 5kW because you would have to have: · No shadowing of any of the panels during sunlight hours (like trees, buildings or chimneys.) · All the solar panels face exactly the right angle in relation to the summer solstice midday sun for their position on the planet. (Perfect angle facing south and perfect slope) · solar panels completely clean · the sun is completely unobscured · the Inverter 100% efficient · no other losses due to cables, and equipment, and so on. e) Knowing the above PV limitations professional installers often add extra panels to make up for these losses. (Our inverter allows us to add roughly 28% more panels than its kW rating) f) PV panel installations will produce about one fifth of the power in December compared with what is produced at the peak of summer. g) The electric vehicle and charging from the PV only really work well together if you can have the vehicle plugged in during the day and supply over 3kW from your PV (or a large proportion of that). This is why we went for the biggest PV that would fit on the roof. We then installed a system which 95% of the time only charges the EV when the PV is on and generating over 2kW in winter and 3kW in summer (we have a 13amp charging system). So, if finances cause you to have to consider only a few in my humble opinion AIM first and go APE later. (But prepare the property for the APE works as much as you can). Best of Luck Marvin

Ditto

Hi @markocosic I beg to differ. What you say seems to be right when you do the maths, but in fact this is not what happens. To be clear our electricity diverter (which diverts energy to our immersion heater in our hot water tank) only diverts energy which is not being used and would otherwise be diverted to the main grid. As we do not sell our electricity we direct the energy to the immersion. (In the winter when the hot water tank is up to temperature we redirect to an electric storage heater) This is especially useful during the winter when the ASHP is on. It is normal for an ASHP to 'cycle'. This means it heats up and then stops heating every, what 20 mins or so. When the ASHP is not running in our house we average about 600 Watts but this is not constant ( freezer, fridge on/off, kitchen equipment on/off, and so on.) So in between all these on and off demands are moments when surplus energy goes to the hot water immersion. Also it uses the ASHP less but the immersion more: ASHP £ 3,429. Immersion heater under £100. (or under £500 including diverter) Also we set the immersion at 61 degrees centigrade just to make sure we avoid any legionella issues. Also the higher temperature means that we can store more energy from a sunny day to the next not so sunny day as our tank will last the two of us for about 3 days: A day when all the electricity used to heat the water via our ASHP would come from the grid. Since the end of October we have used the ASHP about 4 times to heat the water when there was not enough sun. Oh, and we charge the car during the day when available as well. Hopefully anyone reading this who has PV and a hot water tank with an immersion will check out what I am saying. It is 8.54am and right now the PV is heating our hot water. Marvin

Hi @sharpener We have a Cool Energy inverTech Air Source Heat Pump CE-iVT9 4.3kW-9.5kW with the buffer tank installed using the 3 pipe connection. As has been said it adds to the volume of the system. Our buffer tank is within our thermal envelope and acts a bit as a radiator so any heat we loose is still used. We have a bypass valve on the pumped radiator circuit. Marvin

As I understand it some DNO's have previously permitted the equipment being "limited", however, whether this is still so or not I don't know. In my understanding, as a basic principle if the battery supply is controlled through the approved inverter and then to the mains then ok. If the battery supply avoids the approved inverter or goes through another inverter and is connected to the mains, then need to apply to DNO.

+1 and in between the ASHP cycles you can use a diverter and heat your water.

Hi @dpjjones Aim to go APE It worth considering all the AIM and APE elements before making decisions. That is Airtightness, Insulation, Mechanical Ventilation with Heat Recovery OR Heat pump Ventilation, and Air Source Heat Pump, Photovoltaics and Electric Vehicle. Some of these will not work properly without the others, and some will complement others: A MVHR will not work properly without Airtightness. An Air Source Heat Pump will have to compensate for the lack of Airtightness and/or Insulation to the degree that the benefits become questionable, especially during winter, without them. An ASHP uses electricity and Photovoltaics can supply a little during winter and a lot during summer when cooling can be a problem and an ASHP can supply cooling. PV can supply a little to an Electric Vehicle during winter and plenty during summer if your vehicle is at home during sunny days. Extending a property and only doing AIM works to the extension will be no good, you have to do all the property within the thermal envelope. And thinking of running costs: a) Airtightness and Insulation should have no running costs and last (Well, loft insulation lasts over 40 years, in our experience) with the exception of UPVC units for windows and doors, but that being said it will last 30 years? b) Our MVHR unit servicing 100m2 floor sized home uses about 260kWh a year; far far less than would be used to heat incoming cold fresh air in winter, and we clean the filters twice a year. c) ASHPs are, in my opinion, still in their infancy but we are now in the second year of use here. We were very careful to follow best practice in the design and installation of our system, did a lot of bespoke tweaking, and we now have an upgraded 1970’s timber framed bungalow that uses less than 20kWh per year per m2 of floor for heating. d) PV would be a lot less attractive if there is no ASHP or EV (or battery backup) or diverter to the hot water immersion. In my humble opinion, if you have a suitable roof you should install as much a physically possible. Electricity production costs (cost per kWh) are difficult to evaluate because it depends how much is used and how much is supplied to the grid. We decided to go with the PV cost divided by 7 years, which for us works out at £1.60ish per day. Yesterday the PV produced 12kWh all of which we used. Remember, 5kW of PV panels will not produce 5kW because you would have to have: i. No shadowing of any of the panels during sunlight hours (like trees, buildings or chimneys. ii. All the solar panels face exactly the right angle in relation to the summer solstice midday sun for their position on the planet. (Perfect angle facing south and perfect slope) iii. solar panels completely clean iv. the sun is completely unobscured v. the Inverter is 100% efficient vi. all the other losses due to cables, and equipment, and so on. e) Knowing the above PV limitations professional installers often add extra panels to make up for these losses. (Our inverter allows us to add roughly 28% more panels than its kW rating) f) PV panel installations will produce about one fifth of the power in December compared with what is produced at the peak of summer. g) The electric vehicle and charging from the PV only really work well together if you can have the vehicle plugged in during the day and supply over 3kW from your PV (or a large proportion of that). This is why we went for the biggest PV that would fit on the roof. We then installed a system which 95% of the time only charges the EV when the PV is on and generating over 2kW in winter and 3kW in summer (we have a 13amp charging system). So, if finances cause you to have to consider only a few in my humble opinion AIM first and go APE later. (But prepare the property for the APE works as much as you can). Best of Luck Marvin

Hi @ReedRichards A 22mm copper pipe has an internal volume of about 0.31 litres per meter. Three meters between tank and shower? There's something wrong. In my humble opinion, either long pipework or low pressure or low temperature, or lack of insulation or shower controls interfering. M

Hi @Shaun McD Welcome! Don't forget about airtightness....

Hi @STEVEBAN Welcome. Yes, lots of skilled and experienced people here, oh, and me.

The roof vent has not been trimmed to fit the tile spacing

Hi @Saul Photos a little further back will bring it more into context. Is there any sealant between the window frame and the brickwork?

In my humble opinion: For all those entering the world of improving there home: Aim to go APE It worth considering all the AIM and APE elements before making decisions. That is Airtightness, Insulation, Mechanical Ventilation with Heat Recovery OR Heat pump Ventilation, and Air Source Heat Pump, Photovoltaics and Electric Vehicle. Some of these will not work properly without the others, and some will complement others: A MVHR will not work properly without Airtightness. An Air Source Heat Pump will have to compensate for the lack of Airtightness and/or Insulation to the degree that the benefits become questionable, especially during winter, without them. An ASHP uses electricity and Photovoltaics can supply a little during winter and a lot during summer when cooling can be a problem and an ASHP can supply cooling. PV can supply a little to an Electric Vehicle during winter and plenty during summer if your vehicle is at home during sunny days. Extending a property and only doing AIM works to the extension will be no good, you have to do all the property within the thermal envelope. And thinking of running costs: a) Airtightness and Insulation should have no running costs and last (Well, loft insulation lasts over 40 years, in our experience) with the exception of UPVC units for windows and doors, but that being said it will last 30 years? b) Our MVHR unit servicing 100m2 floor sized home uses about 260kWh a year; far far less than would be used to heat incoming cold fresh air in winter, and we clean the filters twice a year. c) ASHPs are, in my opinion, still in their infancy but we are now in the second year of use here. We were very careful to follow best practice in the design and installation of our system, did a lot of bespoke tweaking, and we now have an upgraded 1970’s timber framed bungalow that uses less than 20kWh per year per m2 of floor for heating. d) PV would be a lot less attractive if there is no ASHP or EV (or battery backup) or diverter to the hot water immersion. In my humble opinion, if you have a suitable roof you should install as much a physically possible. Electricity production costs (cost per kWh) are difficult to evaluate because it depends how much is used and how much is supplied to the grid. We decided to go with the PV cost divided by 7 years, which for us works out at £1.60ish per day. Yesterday the PV produced 12kWh all of which we used. Remember, 5kW of PV panels will not produce 5kW because you would have to have: i. No shadowing of any of the panels during sunlight hours (like trees, buildings or chimneys. ii. All the solar panels face exactly the right angle in relation to the summer solstice midday sun for their position on the planet. (Perfect angle facing south and perfect slope) iii. solar panels completely clean iv. the sun is completely unobscured v. the Inverter is 100% efficient vi. all the other losses due to cables, and equipment, and so on. e) Knowing the above PV limitations professional installers often add extra panels to make up for these losses. (Our inverter allows us to add roughly 28% more panels than its kW rating) f) PV panel installations will produce about one fifth of the power in the winter compared with what is produced in the height of summer. g) The electric vehicle and charging from the PV only really works together if you can have the vehicle plugged in during the day and supply over 3kW from your PV (or a large proportion of that). This is why we went for the biggest PV that would fit on the roof. We then installed a system which only charges the when the PV is on and generating over 2kW in winter and 3kW in summer. (we have a 13amp charging system). So, if finances cause you to have to consider only a few in my humble opinion AIM first and go APE later. (But prepare the property for the APE works as much as you can). Best of Luck Marvin

The devil is in the detail!!!

Hi @SteamyTea That's interesting. I wait with baited breath to see how this pans out. Most payments made in Dec/Jan 2023 are for tax due on the work in the tax year 2021 to 2022. Interest on money borrowed is now 8 times more expensive than 1 year ago. The UK debt is presently about £2.4 trillion pounds. at 4% that would be about £263,000,000 interest a day.... Luckly most is at a lower rate of about 0.5% so only £32,000,000 a day.

Yes its going down at the moment......

Hi @Furnace You can always use the PHOTOVOLTAIC GEOGRAPHICAL INFORMATION SYSTEM: https://re.jrc.ec.europa.eu/pvg_tools/en/tools.html Mark the exact position of the property on the map first and then fill out details on the right. Good luck Marvin

IMHO. What ever is used needs to have a waterproof coating on top.

In that case I would expect the OSB to have a better compression strength due to the mixed grain and the impurities, like bits of metal, found in it.

check the weight of a sheet of both and compare

I think this may have gone off topic.

Yes just the décor would shock me!