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Potterton EP 4000 battery clicking

Postby SarahSays » Fri Nov 12, 2021 5:14 pm

Hi all
I have a potterton EP 4000 timer - I haven't lived here long but I have noticed it clicks non stop not just when it switches the heating on but this non stop clicking all day all night - I mentioned it to the plumber wwho brushed it off as me being daft about it clicking when it switches the heating on
anyhoo it loses time all day and so I can't have the heating on timer it's currently 9 hours out and when reset it loses time again I got the brush off so,I started looking at it and realised maybe it needs a battery change
I took the front off it has a slot for a battery but no battery inside it.
I have been looking for a battey and it took me to a listing on eBy I checked with the seller but he doesn't know if it will fit can anyone kindly direct me to either a link or the exact words I need to find said battery.
thanks kindly :)
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Postby ericmark » Sat Nov 13, 2021 12:30 am

There are it seems more than one model with same name, however it should work without a battery, so likely adding a battery will not help, likely whole unit needs replacing.

We tend not to use programmers any more, don't really want to turn heating off, we just turn it down, so a programmable thermostat is the normal way.

I still have pure time for domestic hot water, 1/2 hour every other day, as I have no tank thermostat, if I had a tank thermostat then it would just be left on.

So does your timer also do DHW? If not then renew the wall thermostat with a programmable type and switch CH on all the time.
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Postby SarahSays » Sat Nov 13, 2021 4:37 am

oh :( I don't know what DHW is ?
I am a woman of many means but central heating isn't one of them ..
it is old but the landlord won't replace anything and yes I am wholly aware of my rights and how wrong and immoral and illegal it is but all I can do is get by for the time being.
When I first moved in I hd the plumber in for another issue and asked about the clicking and he just sighed and said it was manual thing so it will click and the whole street has the same thing and they're not really ideal forr the houses as they don't create enough hot water for a famil's needs or something ?
when I was looking up the issue it was suggested the battery needed replacing so I hoped it was the fix but obviously not the lady who lived here before told me she had the same issues and just manully over rode it - thank you for your clear reply
the pump was just replaced the tank was clanging that took 2 months and in the end I called someone out myself when it was clear the landlord wasn't going to do anything and either ignored my calls o just kept saying he was trying t book someone
I don't really understand how it works and feel a bit daft but there's a boiler recently replaced in the garage hot waters is on all the time
the house runs warm so I am happy just turning on the heating for a couple of hours a day
it has two timers for it to be on at set times but as it's losing time I have to just manually over ride for the heating - however the heating isn't working upstairs at all and won't turn off unless I switch the switch in the hot wter tank cupboard upstairs and power it off
so, I guess it's come to the end of it's life span ... is it big job ?
I have a friend who is pretty handy does lot of labouring and plumbing work but not sure if it's too big a thing to ask for or if I can just use heaters and switch it off and suck it up til I move in the spring.
again thanks for the concise reply vey appreciated :)
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Postby ericmark » Mon Nov 15, 2021 11:33 am

Sorry DHW is domestic hot water.

It seems likely you have a combi boiler so domestic hot water is on demand, no timer for that.

New gas boilers (not oil) are modulating (that means it can turn down output) and gain the latent heat, (energy used to turn water into steam) and to do that the return water temperature is critical.

So basic idea is water to all radiators and as they heat up room to connect temperature the TRV (thermostatic radiator valve) turns down and finally off, and the water is either forced through remaining radiators or lifts the by pass valve, so the return water would if the boiler did not turn down get hotter and hotter, so the boiler monitors return water temperature and reduces output (modulates) until it can't turn down any more, then it starts to switch off/on (mark/space ratio) further reducing output.

The anti-cycle software monitors how fast hot water is returned when it turns on, and adjusts the off time depending on that.

So in theory you don't need a wall thermostat, the TRV does it all, however.

For the TRV to work also the lock shield valve (tap other side of radiator) also needs setting correctly, if open too much the radiator gets stinking hot before the TRV can close, and also likely some radiators will not get hot.

The plumber uses a differential thermometer to set the lock shield valve so 15 degs C difference between in and out pipes, not really some thing you can do DIY.

However closing the lock shield valve completely starting with radiator closest to boiler letting pipes cool then opening little bit at a time until just feel a little warmth, and slowly moving away from boiler will normally get them near enough.

With a TRV marked *123456 normally half way between 2 and 3 will be around 20 degs C I have swapped my heads [attachment=0]61dmtMm13BL.jpg[/attachment] and I can set temperature in degs C and also the time, the advantage is the heads shown cost just £15 and they simply screw on instead of originals so easy to fit, and also easy to remove and refit old type when you go.

Not ideal would be better to get timer working, but even with boiler cycling when you are away, still likely cheaper than using electric to heat with. Mine called eQ-3 there is also Terrier i30 prices seem to have gone up since brexit, the eQ-3 I have is bluetooth so can adjust with phone, but so easy to adjust direct, I only use phone to set schedule, easier with phone but can be done without.

It does depend on the home, my three story house takes long time to heat and cool, and I am retired, so don't turn heating off, last house had a 3.5 kW fan assisted radiator plus 3 kW standard radiator and a 4.5 kW gas fire in the living room, from stone cold to 20 degs C less than 20 minutes even on coldest day, often less than 10 minutes, so we never bothered with timers or geofencing (heating turns on automatic as your mobile phone gets close to home) we just turned it one when we got home.

A fan heater is fast, but an inferred heater is instant, but line of sight, also if pointed at windows it goes through windows without heating room, but a fan heater or inferred heater while waiting for central heating to warm home may be worth thinking about.

Since this house is mine, I fitted Nest Gen 3 thermostat, not the best, but it does auto turn on heating before I get home, and auto turn it off when it detects both mine and wife's mobile phones are not in the house. But at over £200 not something you would want to fit, if even permitted.

All central heating is a compromise, yes we could have all fan assisted radiators with a heat pump which both heats and cools the home as required, but the installation cost is silly, so we use near enough engineering.

My heating is not perfect, but much improved since buying house, how the last owners put up with if I don't know, had to go outside down a set of steps and back into flat under main house and plug in the pump, there was no thermostat, and the timer did not turn pump on/off only the boiler.

I likely spend around £800 to get it all working, now I can sit at this laptop and turn the heating on/off around the world, but can't really expect a landlord to pay out that sort of money to automate the system.

But the moes thermostat is quite cheap, that is also wifi enabled, £20 approx, so maybe you can strike a deal, you buy it, he gets it fitted, if he things he is getting some thing free he may go for it?
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