Hot water too hot Worcester danesmoor 15 19

18 Nov 2023
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United Kingdom
I've recently moved into rental property and when turning on the hot water I'm finding it absolutely boiling. It's a Worcester danesmoor oil fire boiler. Any help would be great. Thanks
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Google your make and model. There's usually a means of reducing the water temp. You won't need to start taking the thing apart, it's a standard user-control. You want it at about 55 degs max. Note, a shower is usually no more than 42 degs.

If you're still struggling and confused then speak to your Landlord / agent (whoever checked you in). They'll want you to be happy and safe living there.
On the front panel there should be a temperature dial.
If the burner is running, turning it down should shut it off. Likewise, if the burner is off, turning the thing up should give a click and the burner should cut in.
Is it doing this?
To lower the water temperature in your Worcester Danesmoor oil boiler, you can follow these:

Check the Thermostat Settings: Ensure the thermostat on your boiler is set to the desired lower temperature. Most boilers have a thermostat that allows you to adjust the temperature.

Use an External Thermostat: If your boiler doesn't have a built-in thermostat, consider installing an external thermostat to control the water temperature.

Consult the User Manual: Refer to the user manual for your specific Worcester Danesmoor model. It often contains information on adjusting the water temperature settings.

Call a Professional: If you're unsure about making adjustments or if the issue persists, it's advisable to contact a professional technician. They can assess your boiler, make the necessary adjustments, and ensure it operates safely.
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The central heating systems in the UK are given plan names, we have C, S, Y and W as main plans, the C and Y plan is favoured with the oil boiler as the water can cool by heating the domestic hot water (DHW) once boiler is switched off. There is a dial on the front of the boiler to adjust maximum heat, but this also controls temperature to the central heating (CH) you can get in pipe mixer valves used in old peoples homes and hotels to reduce the temperature in the taps, but there is little one can do to regulate water temperature in the storage tank.

The C Plan means DHW is heated using thermal syphon not the pump, which is why it is used, as once the power to boiler is off, it is still allowing boiler to cool by heating the DHW, there were for gas boilers three options with C Plan, by fitting a tank thermostat in summer you could set the boiler to only fire when required, so saving oil/gas but in winter they do nothing, and by adding a tank thermostat and motorised valve, they can control the DHW temperature both summer and winter, but this is not liked as it can stress the oil boiler when no where for heat to go once switched off, was only done with gas boilers.

The other plan the Y plan is much better, as default is DHW on, so boiler can cool, but running the motorised valve can turn off the domestic hot water, the valve it powered to turn the DHW off, not on, so the tank stat and programmer need to use the normally closed contact as well as normally open contact, and I have seen it where the wire has not been fitted.

With oil the combi boiler is not like the gas version, you can't turn down the boiler output like with gas, so it works on a mark/space ratio, turning off/on to regulate output, so there needs to be a water store, it may be inside the boiler, but it still has a water store.

I have a Worcester danesmoor oil fire boiler, but it seems there are many versions, mine it rather basic, and it works well, all controls are exterior to the boiler, all need to be supplied from the same fused connection unit (FCU) so that with a power cut the solar panels and battery back-up can still power all items of the central heating, so to alter the system to control the DHW temperature would be rather expensive. However in the summer months the boiler is turned off, and my DHW is heated with excess solar using an iboost+, before the solar panels I used simple time in the summer, ½ hour every other day, a bit hit and miss, but the cost to fit a thermostat to the water tank is expensive, as was the solar panels, but they will if I live long enough pay for themselves.

I would think the chances of a landlord paying out to reduce the water temperature is slim, so if C Plan then either you live in a cool house with cool hot water, or a warm house with very hot hot water, no real option to do anything. But if it is a Y Plan (uses three port valve) then there well may be an adjustment, if a S Plan (uses two x two port valves) again likely can be adjusted.

Is there some thing like this 1705845691088.png on the hot water tank? Do you even have a hot water tank or is it inside the boiler?
It seems I have made an error, Part G of building regulations it seems from this video
gives maximum temperatures, page 18 of this document state
(4) The hot water supply to any fixed bath must be so designed and installed as to incorporate measures to ensure that the temperature of the water that can be delivered to that bath does not exceed 48˚C.
I was unaware of this, so it is unlikely one can ensure the bath does not overheat without also the whole house. However it does also say
Requirement G3(4) applies only when a dwelling is—
(a) erected;
(b) formed by a material change of use within the meaning of regulation 5(a) or (b).
So it would seem only valid if central heating is changed. I remember many years ago being told by my Uncle not to wait for the hot water to arrive at the bath, as I would only need to add cold latter. And the water in the hot pipes is warmer than that in the cold pipes, and so less likely to run out of hot water.

This house I don't think I could fill a bath with hot water in the summer, the immersion heater is too short, I would need to run the central heating boiler, but only had one bath in 4 years, normally shower, so not a problem.