Confusing hot water boiler set up, need help programming

nalted

Hello, some background: I am a novice at house related things, as im a 20 yr old uni student in newbuild uni house, with 6 other housemates (7 total). As of 29th October, our bills shot up like crazy, from an average of 17.25 kWh of daily electric usage, to now 56.9 kWh per day. We believe to have diagnosed it to be our water boiler. We are not sure why it suddenly changed on the 29th October, but we believe it for some reason is on all the time instead of turning on at programmed times. We know how to turn it off entirely, and how to turn it on, but not how to program it.

I have attached pictures of the set up so that anyone who may recognise how to use it may help. The only thing I can see that *might* program it is the ESI esrtp4rf+ thermostat, as its seemingly connected to the water boiler (in pictures), even though we have a separate gas unit for house heating, and even though online documentation specifies that the ESI thermostat is used solely for the central heating too. Other than that, we have no idea how it works and why it has suddenly gone insane.

I plead for your help, as our student house leasing company are terrible and ignore our cries for maintenance help, by the time it comes, we will be a few hundred pounds down again.

Note : The fifth picture is our Intergas Compact HRE 30 SB gas boiler, don't think its involved in this issue, but thought i'd attach anyways.

Jamie Hall

I doubt that the increased apparent usage has anything to do with the gas heater. They use very little power!

But, before we start really worrying about the water heater — boiler — you need to be quite sure that there are no other uses which might have changed. I'm sure you have done that, but it's best to check. For instance, are there any electric space heaters in your flat? Just one could easily account for at least half of that change. Has there been any change in hot water use? Is your cooker electric? Has there been any change in that use?

Once you get all that sort of detective work out of the way, do you actually have a way to see current electrical use? Is your meter set up that way, or do you have to count on a bill? There have been instances — I forget where now, but I think perhaps in Northumberland? — where some of the new "smart" meters have been none too accurate. Might look into that. In any event, if you can see an actual daily use, or better a real time usage, try turning the water boiler off for a whole day (yeah, I know, cold showers. Sorry…) and see what difference that makes.

I'm sure you've done at least some of this, but it won't hurt to repeat…

Then if it does turn out to be the boiler, we can begin to figure out what's happening.

nalted

Hello,
Thanks for the reply! We had assumed it was the water as our energy company gives us a breakdown of our energy. I'll attach screenshots. 902 kWh in Nov vs 333 kWh in Oct.

bburd

That knob near the base of the boiler (water heater) is the thermostat. It is set to the maximum, 65° C. It also may not be very accurate.

I am in North America and do not know UK codes or practice, but here 140° F (60° C) is recommended as a safe storage temperature to prevent the growth of legionella bacteria; this requires a mixing valve at the outlet of the water heater so the temperature at the tap is a maximum of 125° F (51°C) which is less likely to scald people.

As a first step, turn down that thermostat! You might also want to get a thermometer and check the actual temperature at the taps.

Otherwise, try to use less hot water. Shorter showers, care when washing dishes, use warm or cold settings instead of hot on clothes washer.

The breakdown of your energy usage is based on an algorithm and may not be very accurate either.

Your separate gas boiler for space heating and the space heating thermostat almost certainly have nothing to do with this problem.

GGross

Did you get an additional tenant on or around the time the usage changed, or is there another attached unit that might have had someone move in?

HVACNUT

What's the "Alway on" listed on the charts? Looks like a thermostat. It went from 38 to 81 kWh, but the percentage dropped? I can't see it well. And the water heater consumed nearly triple the energy, but accounted for a 4% drop in overall usage? I'm bad at math.

Jamie Hall

That "smart" meter usage calculation is, at best, a guess depending on a raft of hopeful assumptions made by whoever programmed it. Pretty close to worthless…

hot_rod

it looks like some sort of indirect tank with electric backup? Based on the piping and zone valves

jesmed1

@hot_rod seems to have the right answer.

According to this web page, your indirect water heater (the big white Tempest tank) has a 3kW electric coil installed for "backup" heating. For whatever reason, the 3kW backup electric coil is probably running too much and causing your high electricity usage.

https://www.telford-group.com/product/tempest-stainless

hot_rod

In some commercial applications they get better kWh rates off peak. That element may have a control, know as a dual fuel, to take advantage of the lowest cost energy.

It could be mis-programed, disconnected, ??

Somehow you want to find out the control logic. To see when and how the element is kicked on.