Heat pumps

matt_drummer

Reed_Richards said:

matt_drummer said:

I have no export limitation.

I export about 9 kWh at the peak from the solar panels.

That's very fortunate.  But surely your DNO must have set some limit?  In principle you might export simultaneously from your panels and from your battery and blow the mains fuse?

No, no export limit.

The limit is imposed by the equipment I have, which they have approved.

In theory my export could be around 16 kWh but that is not going to blow a 100 amp main fuse.


I had my main fuse changed from 60 amp to 100 amp a few weeks ago.

I was talking to the engineers from the DNO who came to change the fuse and expressed my concerns about the 60 amp fuse.

They told me my 60 amp fuse could withstand a few hundred amps for a couple of days before it finally melted.

They also told me that their fuse is there purely to protect their equipment, not my house,  and it would take an instantaneous load of a few thousand amps to blow their fuse.

matt_drummer

SeanSocks said:

I applied to BG for a survey. After giving details the Agent quoted me over £6 thousand on top of the Grant. I said that's a bit steep seeing as I won't need bigger Rads. or Pipework(We live in Penzance,it seldom freezes here) .....He answered, "You must have them by Law"...................a couple of weeks later I applied again and got a different agent, same price......but she said I could get a reduction if I do not need bigger Rads. or Pipes......

My Octopus install started today.

The `stuff' arrived in a Luton van, it was pretty full.

It's a lot of gear and just looking at it I can't see how I could buy it myself for anywhere near the £6,700 I am paying.

Taking it all into account, its a bargain.

I can't say it's an entirely painless process, today has been challenging and i expect the next day or two to be difficult to say the least.

But, if you want an ASHP I can't see getting it any cheaper than BG or Octopus are offering using good quality known brands.

All the stuff they are using is good quality and they know what they are doing.

As you might expect, it's the office staff and admin that create a lot of the issues.

As ever with trades people, you have to put up with a certain amount of complaining and manage them to get the best result possible.

I'm not regretting my choice of installer yet but I will be glad when it is done.

Reed_Richards

Try to ensure that you retain independent control of your/one of your immersion heater/s.  My heat pump was installed in mid-December.  After about a day it went wrong.  Because it was in an error state, I lost all control, including the ability to turn on the immersion heater.  Fortunately my installer returned promptly to fix the problem (a blocked filter) and that problem has never recurred.  But I got the wiring changed so I could switch on the immersion heater in case of need (or to soak up excess solar power) without needing to go through the heat pump controller.    

matt_drummer

Reed_Richards said:

Try to ensure that you retain independent control of your/one of your immersion heater/s.  My heat pump was installed in mid-December.  After about a day it went wrong.  Because it was in an error state, I lost all control, including the ability to turn on the immersion heater.  Fortunately my installer returned promptly to fix the problem (a blocked filter) and that problem has never recurred.  But I got the wiring changed so I could switch on the immersion heater in case of need (or to soak up excess solar power) without needing to go through the heat pump controller.    

Thank you for the advice.

I will try and make sure that happens.

oliver1951

Reed I’m sort of surprised that the immersion was set up so that it couldn’t be independently started, esp as normally one would consider this to be its function. Accepting that it’s also used to support the heat pump in heating the water but I would anticipate that should only be when heating the water up to 60 c to do the routine legionella process. If I ever get through planning permission and they can install I’ll bear this in mind.

Matt it’s great to be able to hear the install process from you. I went BG , am nervous so your experience will be helpful. Though as I think I’ve said before I have become embroiled in a lengthy planning permission process. Frustrating. No help from BG either.

matt_drummer

oliver1951 said:

Reed I’m sort of surprised that the immersion was set up so that it couldn’t be independently started, esp as normally one would consider this to be its function. Accepting that it’s also used to support the heat pump in heating the water but I would anticipate that should only be when heating the water up to 60 c to do the routine legionella process. If I ever get through planning permission and they can install I’ll bear this in mind.

Matt it’s great to be able to hear the install process from you. I went BG , am nervous so your experience will be helpful. Though as I think I’ve said before I have become embroiled in a lengthy planning permission process. Frustrating. No help from BG either.

I don't think the experience will be much different with BG. The installers working at my house right now all seem to have worked for BG at some time. I think they just do the rounds!

It's going OK today, so much so I have come to work for a bit.

Reed_Richards

oliver1951 said:

Reed I’m sort of surprised that the immersion was set up so that it couldn’t be independently started, esp as normally one would consider this to be its function. Accepting that it’s also used to support the heat pump in heating the water but I would anticipate that should only be when heating the water up to 60 c to do the routine legionella process. 

Unless I wanted to make the hot water hotter than the recommended 50 C you are correct, the only purpose of the immersion heater as far as the heat pump is concerned is to take the water up to 60 C for a short while to guard against legionella.  I think the problem was probably that the instructions given to the electrician were specific to the needs of the heat pump rather than the wider needs of the household.  

matt_drummer

Reed_Richards said:

Try to ensure that you retain independent control of your/one of your immersion heater/s.  My heat pump was installed in mid-December.  After about a day it went wrong.  Because it was in an error state, I lost all control, including the ability to turn on the immersion heater.  Fortunately my installer returned promptly to fix the problem (a blocked filter) and that problem has never recurred.  But I got the wiring changed so I could switch on the immersion heater in case of need (or to soak up excess solar power) without needing to go through the heat pump controller.    

I went through the immersion heater system with the electrician today. Everything is good and we will have complete control of the system.

Thanks again for the advice.

matt_drummer

Today has gone quite well.

Most of the electrics are done.

The benefit of using your energy supplier to fit the heat pump is that you get so much more than you probably would with an independent installer.

I have had some serious upgrades to my meter cabinet and my smart meter comms hub is now working again.

The guys doing the work all have experience with meter fitting, I'm impressed with the electricians, really good and the works is neat and tidy, top quality from what I can see.

The plumbing side is going well, my old hot water system has gone, the new one is nearly there. The gas boiler has gone and the gas supply will go tomorrow.

The two required radiator changes are done.

We won't need to turn off the water or power again.

They are proving really easy to work with and I am really happy so far.

oliver1951

Just got this from BG. “ In relation to your query, British Gas are not an “accredited competent person that is registered on the GOV competent person scheme list” and therefore we would not be able to sign off on our own work as per the Building Regulations.”
Matt did you have a building regs issue with Octopus?