Economy 7 Suddenly No Hot Water

[joebooooy]

Hey there,

I have a Horstmann Economy 7 hot water system and it has suddenly stopped working.

At first I thought a fuse had gone on the main system, but after checking, it seems that this is not the problem. The light on the timer system comes on when I turn on the off peak 1 hour burst, but the water in the tank does not heat up at all.

Here are two pictures of the system.

Any help would be much appreciate.

Regards,

Joe.

 

[JohnD]

have you got a multimeter, and can you safely test if power is being delivered to the immersion heater?

(a neon screwdriver is not acceptable)

p.s. you could do with splashing out £13 on a new cylinder jacket, too.

 

[joebooooy]

Hey,

Thanks for your reply. I dont have a multimeter to hand at the moment. I will be testing it shortly however.

If the power is getting to the immersion heater, will that mean that I need to replace the heater?

On the other hand, I am assuming that if the power is not getting to the immersion heater, the Horstmann Economy 7 unit is faulty.

Thanks again,

Joe.

 

[JohnD]

probably

if power is going to the immersion but it is not giving heat it might also be that the overheat stat has tripped. Some can be reset.

there is also a chance that the cable draped round the cylinder has been snagged or pulled and has come loose. Why is it blue? Is it heat resistant? Clip it neatly.

 

[joebooooy]

I'm not really sure why its blue, I moved into the house about 6months ago see.

Ah right, whats the overheat stat? I looked at the top of the immersion heater (under the metal cap) and there is the thermostat control, with a reset option. Is that it?

Joe.

 

[JohnD]

probably. Try resetting it. But be aware that it the main thermostat may have failed. If so, take out the old one and get one of the same type and length that will swap in. Note the brand and any other markings on the heater cap as that will help you find the matching stat.

You do not have to drain the cylinder to change the thermostat as it is in a watertight pocket.

The heating element, however, is in the water, but so far we haven't found a fault on it.

 

[joebooooy]

I tried pressing the reset button on the thermostat on the immersion heater but that didnt seem to work.

Do you know where I could pick up a replacement thermostat? I checked on screwfix.com and the replacement immersion heaters themselves are only £16.99.

Cheers,

Joe.

 

[JohnD]

take out the old thermostat and take it with you to your nearest supplier (DIY shed, plumbers merchant, electrical supplier). Note the brand of heater.

Although a new element is not very expensive, it is a lot more work to change (you will also need the big box spanner; and the old one might be jammed in and damage the cylinder taking it out

If you do decide to buy a new element, get the Incalloy one, it lasts longer.

Buy yourself some heat-resisting Immersion Heater cable while you're there, and some cable clips for it. You would also benefit from a new insulating jacket (you can put it on top of the old one)

 

[joebooooy]

Cheers for all of your help, this is my first time posting on a DIY forum and its been really helpful.

I think B&Q have the replacement thermostats, as well as the Incolloy immersion heaters, complete with thermostat. I'll probably pick up both just incase!

Thanks again John,

Joe.

 

[joebooooy]

Actually, taking the thermostat out and clicking the reset button seems to have worked! The boiler is warm and there's hot water coming out of the taps!

Hoorah!

I've set the off peak times for tomorrow morning at 3-8 so fingers crossed!

Cheers.

 

[gas4you]

Bit confused here. It looks like a standard single immersion heater. If so why have you a dual timer?

Usually these are fitted to a dual element immersion, so the longer element heats up the water during the E7 period and the shorter top up element only comes on for the 1 hour boost.

Have I missed something in your picture?

 

[JohnD]

good point

a picture of the meter and consumer unit(s) would help

but maybe it's one of these tariffs where all off-peak electricity used is charged at lower rate, on same circuits.

 

[joebooooy]

Hey, thanks for your response.

That is the way it was set up when I moved in a late last year. I've never had an immersion heater before, or economy 7 for that matter and didnt realise that there should be a seperate heater for each dial.

Is this a bad thing? The house is fairly small and not alot of hot water gets used, just for dishes, and the occasional bath. I have electric showers units for shower time.

 

[JohnD]

photo! photo!

 

[joebooooy]

Hey, sorry, what exactly would you like a photo of?

As far as the economy 7 water heating goes, thats all that seems to be there, the Horstmann Economy 7 timer, and the cylinder with the immersion heater on.

Cheers.