FAQ

Technical FAQs for Fitting of Domestic Immersion Heaters

Q. How do I measure the BSP Thread Size of my Immersion Heater?

A.

 

 


 

If you are encountering problems and need assistance please contact our sales depatment on 01709 828292 or email directly sales@backer.co.uk, we shall try to solve and do our upmost to resolve any problems / query you may have.

General FAQs

What if I don't know the part number for the element I need to replace?

We are aware of most elements on the market, but should we not be able to determine your requirement, then upon receipt of a picture, or technical drawing (including measurements of the element), we can investigate and identify it. Please email relevant details to sales@backer.co.uk

No Temperature Marking on Thermostat

With the temperature marking it was expected that an exact temperature would be maintained however this was for reference only. We now only use " + or - " to increase the temperature turn Anti-Clockwise to reduce the temperature turn Clockwise
Please note the maximum temperature will be approx 70 degree C
Do not over turn past the adjuster stop.

My immersion Heater keeps Tripping and I have to reset

Rod type Thermostats do need adjusting from time to time . To reduce water temperature turn the adjuster knob clockwise . This hopefully should over come the problem.

To find the Thread Size on the Immersion Heater brass boss

Domestic immersion heaters have a BSP thread size on the brass boss. The measurement across the diameter of the boss is approx 1/4" inches (7 mm)
larger than the BSP thread size.

- Example

- 2 1/4" inch BSP diameter approx 2 1/2" inches.

- 2 1/4" inch BSP diameter approx 64 mm 

Technical FAQs

No Temperature Marking on thermostat

With the temperature marking it was expected that an exact temperature would be maintained however this was for reference only. We now only use " + or - ". To increase the temperature turn Anti-Clockwise to reduce the temperature turn Clockwise

Please note the maximum temperature will be approx 70 degree C

Do not over turn past the adjuster stop. 

Why was the old immersion heater giving hotter water and now the new one is cooler

The EN standard means that we cannot allow the upper limit of the control thermostat circuit to rise above 70/75 Degrees C as this will cause ambient temperature problems with nuisance tripping on the secondary safety cut-outouts circuit.

Why is the water just getting warm and not hot

Try increasing the temperature that the thermostat is set to, turn the adjuster knob Anti-Clockwise but please ensure that the correct size of element has been fitted to the cylinder

My Immersion Heater Keeps Tripping and have to Reset

Rod type Thermostats do need adjusting from time to time

To reduce the water temperature turn the adjuster knob clockwise this hopfully should over come the problem.

Can a Thermostat be changed without draining the complete Cylinder?

Yes

1. Ensure the power supply is isolated before removing the immersion heater cover.

2. Disconnect the electrical connections from the thermostat body.

3. Carefully withdraw the thermostat and replace with a suitable new thermostat

4. Reconnect the electrical connections,ensuring these are adequately secured

Note – With Plug in thermostats resistance will be felt when with removing the faulty thermostat, care should be taken not to twist the thermostat from side to side during its removal. When replacing the plug thermostat with a replacement care must be taken to ensure correct location of the male tag into the tightened female Tag.

What are the temperature setting on a Cotherm TSE 00187 Thermostat?

1 = 10°C

2 = 25°C

3 = 40°C

4 = 55°C 

5 = 70°C

How do I connect the wiring to a Cotherm TSE00187 Thermostat?

A = Live (Brown)  

B = Neutral (Blue)

Is there a reset button on a Cotherm TSE00187 Thermostat?

Yes It is situated above the number 1 on the temperature scale and is marked (Safety)

What are the temperature settings on a Thermowatt RTS3 Thermostat?

Operating Trip – Single Dot is the lower limit and Double Dot is the higher limit.

1. Red Dial 52° – 60°C (75°C Safety Cut-Out)

2. Blue Dial 63° – 71°C (85°C Safety Cut-Out)

3. Yellow Dial 52° – 60°C (70°C Safety Cut-Out)

4. RTS Plus 52° – 60°C (90°C Safety Cut-Out)

Is there a reset Button on a Thermowatt RTS3 Thermostat?

Yes it is situated in a small recess above the temperature control dial

My Immersion Heater needs replacing how I know what to buy?

All our Immersion heaters have a product code either on the side wall
of the cover or on the top of the cover. This code will be a series of
letters and numbers please see images.

Do all domestic Immersion Heaters require a second level of protection against over temperature operation?

Yes this can take 3 different forms.

1. Single Dual function thermostat

2. Single control thermostat and separate over temperature manual reset button cut out.

3. Single control thermostat with a second manual reset over temperature thermostat.

I can not find the product code for my immersion heater what information do I need to purchase the correct replacement?

You will need to know the length of your immersion heater, the
Power rating in watts, the size of the thread of the brass boss and
whether your hot water system is vented or unvented.

How do I tell if my hot water system is vented or unvented?

Unvented cylinders work directly from the mains supply of water and are
essentially a hot water storage cylinder; where as vented cylinders are
connected, via a vent pipe, to the cold water storage tank which
is usually located within the loft space of most properties.

How do I know the Size of the thread on my immersion heater brass boss?

All domestic immersion heaters have a BSP thread size on the brass boss.
The actual measurement across the diameter of this boss is 0.25
inches larger than the stated BSP thread size. 

How do I find out the length of my immersion heater?

The only way to be certain of the length of your immersion heater is to measure from the underside of the brass boss to the end of the heating element. However if your immersion heater is fitted in the side wall of your hot water cylinder (horizontally) then it will usually have a length of between 11 and 16 inches. If it is fitted to the top of
your hot water cylinder (vertically) then it usually has a length of 18
to 36 inches dependant on the size of your hot water cylinder.

My Immersion heater is not working – How do I know what’s wrong?

There are 5 possible reasons for the immersion heater to stop working.

1. There is no electricity supply to the immersion heater.

2. The over temperature trip in your Immersion heater”s thermostat has cut out.

3. The thermostat in your immersion heater is faulty.

4. The immersion heater has failed to earth.

5. The immersion heater has gone open circuit.