What kind of boiler is this? And how do I change water temperature?

[Simon Ferrol]

Just moved into new Council flat. This is a high rise estate where they have a central boiler providing gas and heating to the whole of the building (or so I was told) , then each flat has a second boiler, basically reheating water and heaters (??? That's what the housing officer told me). I pay gas through a meter card but I cannot change the provider. This is the best information I got from the Council.

In any case, I do have a boiler at home, but it lacks all controls. I need to lower the water temperature as it literally boils my hands, even after mixing.

The boiler is a Worchester (Bosch). I can only see:

Typ 775 3045767 OMS Radio+ 868

After some googling, I think this is it:

But I still don't understand how to manipulate the water temperature.The boiler has an LCD display but there's no way to change the settings.

Then there are two wireless thermostats, one called EPH-TRFI, that looks like this:

The other is a Pipit 500 that looks like this: These two look like they have something to do with room temperature but not water temperature.

Does anybody have a clue?

SF

[Andy Burns]

I wouldn't really call that a "boiler" it's just two heat-exchangers one for your DHW, the other for CH.

Apparently the DHW is preset to 50°C, find out whether you're allowed to adjust it, looks like the upper "TRV type device" shown on page 6 of the PDF you linked.

"The temperature of the domestic hot water is controlled by a thermostat**. Using a sensor, this thermostat controls the temperature of the domestic hot water that exits the heat exchanger by regulating the primary flow through the DHW heat exchanger via the priority valve."

[Robin]

I don't think /you/ are meant to adjust the temperature: "Concealed Allen screw secures casing" that "Deters tampering and helps prevent end user contact with heated components"

Bear in mind the council may have sealed it to detect people fiddling their bills.

In any event, water at 50 degrees is hot. (Hotter than recommended for old people.) If you've been used to cooler it may feel dangerously hot to you.

Assuming you don't have a thermometer to check it, can you mix 200 ml of boiling water with 300ml of water from the cold tap and comparing that with what comes from your tap?

[weel...]

Not sure if this is the way to do it but I have the lever mixer type, swivel left or right to adjust temp. I set the `swivel lever` mid point and then adjusted the isolation valve to decrease the amount of flow of hot water to the mixer tap, so I now have an acceptable temp when tap lever set at mid point.

[Theo]

The manual "The priority valve in the pressure temperature control valve [2] ensures that maximum output is used for providing DHW by isolating the space heating when a hot tap is open. The temperature of the DHW is controlled by the thermostatic head which closes down the pressure temperature control valve [2] if the set temperature is exceeded."

So it appears there's a TRV-like head inside that sets the temperature. On the picture on page 6 there are two - the white beehive-like object in the middle of the unit which appears to be this head.

However the unit is probably preset to 50C to avoid problems with legionella (while at the same time optimising efficiency of heat transfer), so it would be inadvisable to set it lower. I think the solution here would be to install mixer taps so the water coming out of the taps could be cooler.

In care homes they have thermostatic mixers under the sink/bath/etc so the water coming out of the hot tap is never more than 40C (or thereabouts), which is an option if the sink/etc porcelain can't take a mixer tap.

Theo

[Andy Burns]

Is legionella an issue in systems that don't store water?

Does the council permit changing the taps?

[Robin]

which prompts a question for Simon:

Do you have bath with a thermostatic valve* that limits the temperature of the water? If so, how does the water from that compare with other taps?

*They've been common in social housing for a long time, and compulsory for the last 10 or so. Often have a "stop" at around 40 degrees.

[Robin]

sorry, that shd've been "compulsory IN NEW BUILDS...

[Jack Harry Teesdale]

Why not just blend the water using the individual hot and cold taps to a temperature that is acceptable to you.

If it is a council property, the council may not permit user adjustment on the heating equipment.

[Simon Ferrol]

My combined bath/shower has two taps. One for the intensity of the flush, the other for the temperature, but it was quite hot when I used it the first time. I could set my own mix but I couldn't see a stop at

40 degrees.

Rob>> Theo wrote:

[Simon Ferrol]

Because the bloody taps are far apart.

Harry Teesdale: