Would a bigger pump compensate for small pipes?

[J1mbo]

No, the heat pump itself needs a meter. Normally the installer would just slap a meter on the supply to the consumer unit serving the heat pump, assuming it has one. I wouldn't necessarily contact the RHI scheme tbh since you've signed a declaration saying you have meters installed (i.e. complied with all scheme rules).

 

See here: Key terms explained for the Domestic Renewable Heat Incentive | Ofgem (search standalone metering)

 

"One option for meeting the requirements of heat pump metering for performance is to use a standalone electricity meter. It measures the electricity consumption of your heat pump. The electricity meter will likely have to be purchased in addition to the heat pump, and the meter will need to be installed alongside your heat pump prior to you applying to the scheme.

There are certain technical specifications and accuracy requirements that standalone electricity meters need to meet.

Standalone meters must comply with the specific requirements in the 2014 Measuring Instruments Directive (MID). The meters must fall within accuracy of Class A or better, as defined in Annex V of the MID. (Meters marked class 1 or 2 are not compliant). This will mean that your electricity meter will measure the electricity consumption of your heat pump accurately in isolation from other devices in your home.

The meter(s) will be required to record and display:

• electricity used by the plant to generate heat;
• electrical input into any supplementary electric heater controlled by the same control system as the heat pump; and
• electrical input into any immersion heater for a domestic hot water cylinder where the immersion heater is controlled by the same control system as the heat pump.

This will need to be added on your MCS Certificate."

Edited November 23, 2021 by J1mbo

[Hogboon]

More 'strewth - but this time spelled with a eff. My 'contact' with RHI, if such it turns out to be, was via a friend who tells me that, according to them, they aim to respond within 10 working days, so I shan't hold my breath. Have meanwhile fired a broadside at the installer and await a response. 

[Hogboon]

Installer's response:

 

Quote

There is a meter installed to record electricity used by the heat pump, it's a requirement that this is fitted from March 2019.

 

If you want to measure the SCOP (Efficiency) of the pump this can be done by installing the additional LG equipment, more than happy to quote you for this.

 

I have asked for its location. What the "additional LG equipment" might be I have no idea unless it is LG's PENKTH000 mentioned in an earlier post but my understanding from LG was this form of metering was unacceptable for RHI. If it's unacceptable to them why would I want it? I'm not doing any of this for fun! I don't want to "measure SCOP" etc but do want to know if the heatpump is performing efficiently etc. Currently there seems no way of telling, but if the metering required for RHI is installed then presumably that could tell me what I want to know. Right now the heatpump is still churning away trying to raise the house temp from 17.6º at 07:00 to 20º. Current temp [at 12:45] still only 19.1º Outdoor temp here [near Taunton] about 8º.    

[Luke1]

Do you not have a secondary meter next to your existing meter? This is what I have and it measures heat pump consumption only.

 

[Hogboon]

Quite right Luke1 ! Had a look and there it is - an Emlite M20. What I had been expecting was something resembling the attached. I assumed that setup was what was required for RHI instead of which there is one small meter 10 feet off the ground in a dusty corner of the garage only frequented by tarantulas. Meanwhile the heatpump seems to have reverted to its old ways. Yesterday started 'chilly' [but above freezing] and thereafter was 8-10º yet the heatpump took from 07:00 till 16:00 to raise the house temp from 17.7º to 20º. As my wife was awol for the whole day there were no additional demands via hot water and the doors and windows were not all open.   

 

I will get back in touch with LG, explain the setup and heat requirements here and see if they have anyone who understands how to configure their equipment. Frankly, I consider yesterday's performance totally inadequate.

[LGMMSP C_10_19v1] LG MMSP Wiring Diagram Plus Cloud Set Up (2020) (1).pdf

[J1mbo]

Re the performance. The controller needs to be in 'auto' mode and it should say auto on the screen I think, in order to use the configured automatic weather curve.

[Hogboon]

Cor blimey ! if that is allowed these p.c. days. It wasn't on 'auto' but now [09:00] is, and icons etc have gone a rather fetching purple which would impress my grand-daughter as it is currently her favourite colour. All other settings remain as before. Thanks for that J1mbo.

[SteamyTea]

46 minutes ago, Hogboon said:

Cor blimey

Only come from the days when blasphemy was an offence.

Just means "God blind me".

[Hogboon]

On 21/11/2021 at 21:13, J1mbo said:

possibly on the main controller there is an 'energy' menu with the electric consumption data: Information Of Meter Interface - LG Therma V series Owner's Manual [Page 36] | ManualsLib

 

As mentioned previously, the menu options on my controller do not include one for 'Energy.' It sounds exactly the sort of thing that is needed so why it is not included on my controller when it is clearly described in the User's Manual is beyond me - like almost everything to do with heatpumps!  The only Menu options on my Controller are for Setting, Schedule, Lock and Timer. The Controller's 'Home' page [if that is what it is called] currently looks like the image below. Should anything there be tweaked? 'Intuitive' is clearly not in the South Korean lexicon. 

  

[Hogboon]

The answer to my opening question "would a bigger pump etc" seems to be "probably not". This post seems to have been based on the false premise that the unsatisfactory performance of my heatpump is due to poor flow - either from small pipes or inadequate pump. So with thanks to all those who stuck their necks out and proffered advice, knowledge, know-how etc and I now draw a line under this post - only to set another hare running under the title "Optimising LG Therma V Controller Settings". You never know; there might be someone 'out there' with a similar installation to mine and a similarly antiquated attitude to thermostat schedules etc who has already invented the wheel, in which case I'd be delighted to hear from you! Ttfn.

[TonyT]

Rather than a bigger pump what about an extra pump.

 

I.e primary and secondary heating pumps, add in a secondary pump energised when the primary is active?

[J1mbo]

You don’t need a bigger pump - the difference between flow and return is already 5 degrees as per the controller.

[ReedRichards]

I have only just found this thread but see here: 

for how the Auto/AI mode works.  In my case (all radiators) the settings (as recommended to the installer) are:

Outdoor Temp for Auto Mode:  Min 5  Max 19

LWT for Auto Mode:                    Min 34 Max 50

 

So if the outdoor temperature is 5 C or less then the Auto mode does not operate and the leaving water temperature target will be 50 C.

 

By the way, my system has two pumps, one inside the Therma V and another for the central heating inside the airing cupboard.  The latter is not at its maximum output speed. 

 

I had to tell my central heating controller that my heat pump was a oil boiler in order to prevent it from short-cycling.