Please HELP, Pulsacoil 2000 Immersion heater not heating. What can I do?

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Immersion heater not working properly switches on at wall both day and night timers green light on boiler is on, but no hot water and no heating/kettling noise from the tank.

Grey tank at the too has 6 inches of water which is fine

Had EDF over who said meter timings / tariff all look good.

Anything i can check / do before calling someone out? Any advice appreciated.
 
Where to start?
1. One or both immersion heater thermostats (ordinary or overheat ones) off?
2. Blender valve on output from cylinder faulty?
3. PCB faulty?
4. Neutral fault on immersion connection(s)?
 
Unless you’re competent with electrics, might as well call someone out.
 
Immersion heater not working properly switches on at wall both day and night timers green light on boiler is on, but no hot water and no heating/kettling noise from the tank.

Grey tank at the too has 6 inches of water which is fine

Had EDF over who said meter timings / tariff all look good.

Anything i can check / do before calling someone out? Any advice appreciated.
Are you trying to use the boiler or the immersion to heat the HW cylinder? If it's the boiler, which has a fault (as you say there is no heating) you could switch on the immersion. If it works, at least you then have hot water while you get the boiler sorted out.
 
Last edited:
"Immersion heater not working properly switches on at wall both day and night timers green light on boiler is on.."

I'm not clear why you are referring to the boiler when your question is apparently about your immersion heater.
If, as is usual, the boiler heats the hot water cylinder via a coil through which hot water in the heating circuit flows, then this is a quite separate system from the immersion heater, which as an enclosed heating element within the water in the cylinder.
The immersion heater is usually considered to be a backup way of getting hot water if the boiler fails.
 
1. The OP has a thermal store, not a standard hot water cylinder.
2. The main volume of the cylinder holds water at around 80 degrees.
3. When hot water is drawn, cold mains water is passed through a coil inside the cylinder (or an external heat exchanger) and picks up heat.
4. The outgoing hot is mixed with cold to achieve the required hot water temperature without causing scalding.
5. It has two immersion heaters, each of which has two thermostats.
6. The lower immersion heater is usually on a lower rate tariff (e.g. Economy 7) and heats the entire cylinder.
7. The upper immersion heater is designed to re-heat the top third (roughly) of the cylinder to provide a boost if the whole cylinder heat level becomes depleted.
8. For each immersion heater:
8.1 There is an ordinary thermostat. This turns the power off once the water at its level reached the desired temperature. It turns the power on again (provided it is required by the programmer and / or the economy tariff is in operation) when the water temperature drops.
8.2 There is an overheat thermostat. This is normally set for a temperature 5 to 10 degrees higher than the ordinary thermostat. If the water reaches this higher temperature it suggests a fault has occurred. The overheat thermostat trips, and doe not reset itself automatically but must be reset by direct intervention. Its usually a red or black button, quite small, which may be recessed into the head of the immersion heater.
9. It would be worth the OP checking that neither of the overheat thermostats has operated, and if either has, it should be reset.
 
The OP has a thermal store, not a standard hot water cylinder.
OK, hadn't spotted that. Am I right thinking it only has immersion heaters, no coil to heat from a boiler? That's what the brochure seems to say, but isn't that missing a trick?
 

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