Off-grid

[norseman]

Thanks for your reply & continued interest C, I'll look into those alternatives. I will also search for an electrician with experience in off-grid, which I suspect won't be easy

nb. I see you reside in Herts, my family roots are in Hatfield & I lived there until the age of 18.

 

[crappy]

No worries. Interest is because I had the same setup as you a few years back - solar charged batteries by day, ran house by night. I'm about to move house and planning a bigger version of it so doing a lot of swatting.
I can recommend a guy who I used last time and again using now. Will send details

 

[norseman]

No worries. Interest is because I had the same setup as you a few years back - solar charged batteries by day, ran house by night. I'm about to move house and planning a bigger version of it so doing a lot of swatting.
I can recommend a guy who I used last time and again using now. Will send details

I took a peek at your recommended contact, but they are solar specialists so not what I'm looking for at this time ... maybe later.
One question I should have asked, with regard to your stated success with a 500w inverter, is what were your earthing arrangements ?

 

[crappy]

Earth? Naaa, that's for sissies

In fairness, that was something I had not appreciated when I initially set it up. My inverters had an earth tab which I grounded to the house supply earth bus. I moved the lighting circuits and low-power plug rings to the new DB which was cross-fed by a change-over contactor which was energised by the inverter. While online, the contactor would pull in, switch said circuits over to inverter. When inverter dropped out due to battery voltage / fault, the contactor would drop out and switch to mains. I had a timer in to stop chatter; the inverter had to be online for 120 seconds before the contactor was energised.
This was a full switch over of L/N. earth always common.

Sorry - you asked about earth

 

[norseman]

Earth? Naaa, that's for sissies

Finally sorted, the boiler is now igniting normally & can be switched between grid/off grid without the need for re-setting. All that was required in the end was a bonding of the earth & neutral on the inverter to keep the boiler's flame failure device happy.
Tomorrow I will fully charge the battery (new in February this year, but only used for tests of the inverter) & we will be prepared for any power cut ... which according to Sod's law may never come, hopefully

I may go down the dual-fuel generator (we have a LPG installation already) route eventually, meantime many thanks for everyone's valuable advice, it has been most appreciated.

nb. Crappy ... I hope the solar planning at your new home goes according to plan.

Regards
N.

 

[Gasguru]

We told you that back in February

 

[norseman]

We told you that back in February

Yes I know you did, but I wanted to try more straightforward possibilities & avoid possible damage to a boiler that is still under warranty.
Even at my age there are still things that I will confidentially dive into, but mains electrics isn't one of them ... so I'm not in the least offended when you say 'I told you so'

Thanks to all once again.

 

[Gasguru]

I'm about to do the same with an old modified UPS I have...we're all turning into preppers.

 

[norseman]

I'm about to do the same with an old modified UPS I have...we're all turning into preppers.

Don't blame you, things are not looking rosy & with winter approaching ...

 

[Raylekkyguy]

Hi AlI, nebie on the site and trying to help, I had the same issue and it took me 12 months to rethink the problem as to why the baxi boiler would not fire up on the inverter... It worked perfectly on grid and 3 inverters later I came to the conclusion it was the inverters did not give enough voltage for the tronics pcb in the boiler to fire up the burner. So how do you get more voltage out of an inverter?
Only follow this suggestion if you understand an confident to do so... My boiler is working perfectly connected to the inverter. No problems at all with my old Potterton Baxi running 24/7
So you may ask how can you get more voltage out of an inverter? It's more simple than you think and only cost me 18 quid. I bought a toroidal 240v to 12 volt transformer, how does this help you ask? Connect the inverter 230 volts into the transformer .. You will get 12 volts out.... Now the leap of faith and trust, you connect only the live 230 volts to one side of the 12 volt secondary input and you will get 250 volts by connecting the boiler supply to Neutral and the other Secondary out, in essence the primary is transforming an additional 12 volts similar to adding 2 batteries together. I used an 80va toroidal transformer because the pcb in the boiler can't cope with the voltage drop when the pump kicks in even if your only turning the HW tap on. Hope this helps R.

 

[norseman]

Too technical for me my inverter has an output of 600w with the capability of twice that figure for a matter of seconds in the event of a start-up surge from something like an electric motor.
Glad you are sorted.

 

[Raylekkyguy]

Hi Norseman, my baxi boiler is fed from a 300 watt Bestec inverter and the inverter also powers the lights and wc fans, the CH doesn't even dim the lights on start up. Putting it in a more simplistic way is to use the 12 volt Ac output of the transformer and adding it to the 230 volts input from the transformer this gives you 245 volts. I will do a scetch on paper and upload a pic and it may help. Regards R.

 

[Raylekkyguy]

It worked for me. I tried every option and this was the solution.Total cost 17 quid

 

[norseman]

It worked for me. I tried every option and this was the solution.Total cost 17 quid

Ours' is a 5 year old Baxi Duo-Tech running LPG.
Total cost for the off-grid back up (110AH leisure battery, 600W inverter & misc. fittings) just short of £300.
I keep a C-Tec charger constantly connected, except when it occasionally serves to charge the car's battery.

Thanks for the sketch.

 

[johnyounger]

I been off grid 13 years in the UK.
Re combi boiler not igniting on a pure sign wave generator. I had the same problem at the start but solved it simply.
My pure sine wave inverter generator has two 13amp 3 pin normal, UK domestic plugs outputs (it's a 1.8kw suitcase module) plug the house in as normal. The other outlet I wired a plug with just an earth and a neutral NO LIVE!!!!
Then I stuck two earth rods in the ground 6 inches apart and connected the earth to one and the neutral to the other.
Dont ask me how or why this works but it does. My brother suggested it, he is an electronic engineer.
He said on grid live and neutral come together or wrap around each other in the power station and off grid this does not happen.
The first inverter I purchased 12 years ago setting always showed and earth fault and no tripping!! As soon as neutral was grounded all was resolved.

Now I have upgraded my system my knew Victron inverter takes care of this an so the neutral is no longer in the ground It will also trip a big diesel generator to charge the batteries when required. When this happens I can't run the boiler and so if I want hot water or central heating during this time, I will completely unplug the house from Victron and batteries and diesel generator and switch to the pure sine wave inverter geni 1.8kw with the earth and neutral in the ground.

So I have the house in no way connected to the national grid but have two armoured cables under ground into the house and one big plug from my so consumer unit so I can run the house from Either system.
Hope that all makes some sort of sense