mk1_man

We find the cool slab on ground floor great when it gets hot, definitely takes the edge of the room temp. Our Vaillant flows around 13 degrees, no issues with any condensation. Although upstairs has overlay ufh the cooling is not that effective so looking to install a couple of traditional air con units whilst we still have the access to run the pipework ( build ongoing ! )

For my situation installing the inverter and batteries has been far more beneficial than installing solar, something I have yet to do. The time when I need the most electric is during the winter when I am using the ASHP the most. Last winter I ran the heat pump and rest of house 24 x 7 at 5p per kWh (TE) and monthly costs were a 1/5 of previous year. The batteries (6 x 5kWh) and inverter (Sunsynk 5kW) were self installed so costs were what I considered very cost effective working out at £120 per kWh. I reckon ROI will be less than 3 years. You can do something similar with a build yourself Seplos 16 kWh battery @ £1500 ( or just £93.75 /kWh) : https://www.fogstar.co.uk/collections/seplos-mason-kits/products/seplos-v4-kit-and-x16-mb31-314ah-grade-a-bundle

whilst cooling my flow goes as low as 12.5 degrees however return is circa 15 so somewhere in the middle. I haven't noticed any condensation anywhere Really impressed how well it works and am sure will be even more impressed once I get my solar installed if the G99 ever comes back!

Hi all, I have used our heat pump to cool house for last three days and I have been blown away how effective it has been. We have the 7kW Vaillant with UFH. It has dropped the internal temperature on the ground floor 2 - 3 degrees which doesn't sound a lot but it has made all the difference. Just wondered who else was doing this?

Hi, I wasn't forced to use the Vaillant cylinder but they weren't happy with the re-heat capacity of my existing cylinder be it had twin coils being a solar cylinder. Instead of trying to fight the point I decided to upgrade cylinder to a ashp compatible version, was originally going with a Joule but found lots of negative feedback about build quality and warranty claim issues. Very happy with the 250l Vaillant, it heats really quickly and retains heat well. I installed it myself and then had it signed off to cover G3 side of things. As long as the Mixergy external plate heat exchanger satisfies mcs requirements then don;t see why it can't be kept.

Hi, not a plumber just a very hands on self builder. what would you like to know? Drop me a pm with your number and I can give you a call if that works better?

I DIY installed my Vaillant Arotherm via an umbrella scheme and it was cost neutral once I received the £7.5k BUS grant. Headline figures were £4k for 7kW heat pump (250 m2 property) , £1k for 250l Vaillant cylinder and £1.6k for umbrella side of things. I did all of the plumbing and electrics and it took me 3 or 4 days off and on, it was fairly simple as already had the underfloor side of things installed, I did take the opportunity to remove the mixer and pump from manifold, also removed all of the actuators. System has been running great with COP in high 4's I used : https://www.air2heat.co.uk/mcs-umbrella-scheme Paul was great, he does a site visit, does the heat loss calcs, all of the BUS application etc. He is also flexible as to what manufacturer you go with and as far as I am aware supports Vaillant, Panasonic, Daiken, Mitsubishi & Samsung. I had already set my heart on the Vaillant but I remember Paul being a huge advocate of the Panasonics. I also understand he supports most of the country but may be wrong. A really nice chap so well worth a call.

Hi, I am just about to move forward with a 28 x 450w panel solar array hooked up to either 2 x Sunsynk 5.5 kW inverters in parallel or a single Sunsynk 8.8 kW inverter. We live in an area with lots of houses and not that many with existing solar so hoping a G99 will be approved with no export limitation. If however there is a limitation how is it enforced / policed? i.e. if you were subsequently to export above and beyond on sunny days who is able to tell? I am looking for SEG payments via MCS sign off. Thanks

Personally I don't see any issue with running flexi's through the cavity wall. Some installs don't offer you the space to have them outside i.e. on out heat pump it is a straight 300mm run and then into the cavity. The picture above suggests same lack of space issue here also. I would however have thought any pipe be it flexi or rigid would certainly need to be correctly insulated when going through the cavity. We used a straight run of Primary Pro straight through. To be honest with our setup we don't even use the flexi's as I was unhappy with the bore reduction. Absolutely no noise / vibration issues either.

Are you able to say what umbrella company? The first I approached were insistent that I needed a 12kW unit when in fact I ended up installing a Vaillant 7kW and it has been great even when sub zero. What type of property do you have and what are floor areas etc. Also is it radiators or underfloor?

15 kWh batteries : https://www.fogstar.co.uk/products/seplos-v4-kit-and-x16-envision-280ah-grade-b-bundle?variant=41838224343099&country=GB&currency=GBP&utm_medium=product_sync&utm_source=google&utm_content=sag_organic&utm_campaign=sag_organic&gad_source=1&gclid=EAIaIQobChMI1ZP7t7CqiwMVRZlQBh2loBGhEAQYBSABEgKh7fD_BwE 5.5 kW Sunsynk hybrid inverter : https://www.cityplumbing.co.uk/p/sunsynk-5-5kw-ecco-single-phase-hybrid-inverter-sun-5k-sg01lp1-eu/p/637259?srsltid=AfmBOorz9B8VK8zh8sbsArz0Xy0x8d7S0UygiiDxk4EZo2Pw2hEBDSdk

I think the £1500 Seplos Mason 15kWh batteries are a great deal. They hook well to the Sunsynk also. I would go this route if I were to start again. The inverter is an easy install all depends where you locate it and the batteries in relation to your consumer unit. Mine are in the garage with simple run to the consumer unit in the utility room : 2 x 15 kWh batteries ( 2 x £1500 ) 5.5kW inverter £1000 Best thing ever.

Hi, yes installed the batteries and inverter (5.5 kW Sunsynk) myself. Really quite simple to do depending on your technical background. As yet haven't informed DNO although I know I should and I will before I install any solar panels. As far as I am aware I am not breaking any laws just their rules. My inverter is set to zero export and also disconnects automatically from grid when it fails to detect a grid present i.e. when there is a power cut etc so very safe. The setup means I have run all Dec and Jan at 5p 24 x 7 instead of 24p - 26p kWh Very happy 🙂

Hi Botusbuild, sounds like you have things sorted now. I installed by Vaillant 7kW and 250l cylinder myself under an umbrella MCS company. I already had underfloor installed (previously on gas) the headline costs were £4k for Vaillant heatpump, £1k for cylinder and £1600 for MCS wrapper so as to access BUS grant. Appreciate not everyone would want to get there hands dirty but I found it really simple and enjoyable and even with all the associated bits and pieces managed to be cost neutral with £7.5k BUS. Running costs have been great at less than £2 per day for the whole house (Nov / Dec) I am on Tomato Energy now at 5p / kWh (with 30kWh batteries) - 250 m2 house similar spec to yours. The MCS Umbrella company I used was www.air2heat.co.uk

I have ground floor manifold covering 150m2 and a 1st floor manifold covering 100m2 and it works great. Primary difference is that I don't have mixer or pumps on the manifolds since installing the ashp and it is much better than when I was running on boiler with the mixers. Simpler is the way forward and also much quieter 🙂