sharpener

Been following this with interest as this is what I am planning/hoping to do. I would certainly not want the HP to cycle off every time the sun goes behind a cloud. I think the battery might be useful for filling in these dips in the PV output rather than time shifting per se. But not so easy to control because (for me at least) the HP will be outside the battery/grid control loop to avoid draining the battery into the HP at other times. Victron control is a bit clunky for this, to prevent discharge you have to set charge periods with an unrealistic target SoC (other solutions are also possible). If and only if there is any export left after all that is it worth using it for resistive heating.

Thanks for all this. Will read the MCS spec with particular attention to the noise requirements, are there any other booby-trap areas it would be wise to follow? Am confident my general plumbing and wiring will pass muster and it will not be a split or need a new HW cylinder so no FGAS or G3 (unless it is required for a buffer tank?) I have got a still open case with Building Control which will cover the HP so a potenial buyer should be happy with that. But judging by their expertise on battery/inverter systems "you clearly know what you are doing and it all looks OK to me" I am not shaking in my boots, they didn't know there was an IET Code of Practice let alone inspect to it. Have been down the insurance on house sale route, the buyer wanted me to insure against the risk that the 1m front fence would be found to infringe a covenant limiting the height to 3 feet dating from when the building plot was sold in 1880 FGS! Cost me £50 so I removed a heated towel rail which wasn't on the list of F&F. Yes, current neighbours had their boiler renewed a few years back. The flue is right in an internal corner, the final section is on the squint, there is pluming past my study window and a smell of gas. Unfortunately they are immune to protests about this kind of thing.

Having a disfunctional LPA myself you have my sympathy and thanks for drawing this to my attention. The Planning Portal says <Development is permitted only if the air source heat pump installation complies with the Microgeneration Certification Scheme Planning Standards (MCS 020) or equivalent standards.> So who decides what are "equivalent standards"? If I produce an elaborate spreadsheet and tell them that in my professional judgement as a Chartered Engineer the MCS standard is not adequate to cover the additional heat sources in my scenario so I have used an appropriate design methodology what will they do? The site adjoins an 'A' road, apart from noise level what possible public harm can there be, the visual intrusion aspect is covered elsewhere anyway.

It's a classic instance of a cartel. If OFGEM were not so useless they would do something about it in the interests of competition. So I am not expecting to find anyone willing to add an ASHP to my present setup, because of the solid walls and my wish to include in the calcs the AGA, the woodburner and the MVHR, and not to rip out much of my existing kit including internet-based controls and a Honeywell Evohome zoning system (no don't start on about zoning, I have my reasons). Howewever even a modest CoP will beat my 28 y/o oil boiler on cost even before factoring in any free PV. Similarly I had great difficulty finding a contractor to install 8 PV panels to wire up to the MPPT on my battery setup because it was not a standard MCS-type installation. Ironically I got an MCS certificate in the end including the notional supply of a meter which never left their stores, because the people I eventually found said they could not issue the certificate without a serial number. No metering required or indeed practiable at 48V DC.

Having read a lot here about the pros and cons of buffer tanks it is clear they result in mixing, which is generally disadvatageous. OTOH they may be a necessary evil to prevent short cyclng. So what do ppl think of the arrangement in the attached Cool Energy installation guide extract? The flow appears to go through the tank but the return does not. Has this got any advantages and would it not be better to have the buffer in the return only as proposed in another thread, and use a conventional automatic bypass valve as a shunt across the rad circuit to maintain the flow rate as zone valves begin to close off the flow? inverTec_Range_Manual_Version_6.6_p9.pdf