immersions in RM stelflow what setting?

[cypher007]

I have a RM stelflow unvented that I have just had fitted. my question is what does the thermostat settings in numbers relate to temperature wise? as it goes 1-6 or something similar not a temperature.

 

[townfanjon]

they are usually Cotherm stats (blue) some are old thermtec (brown and the best)
6 is usually too hot I have tested them at 65 ish degrees, try them at 5 but even those can be too hot for the customer but as we know it should be set at 60.

 

[cypher007]

there set to 3 at the mo, which seems to low.

 

[mfgs]

I normally set them at about 4 or 5 I think. All these new immersions are a pain as they don't state the temperature anymore, which is ridiculous.

 

[cypher007]

I normally set them at about 4 or 5 I think. All these new immersions are a pain as they don't state the temperature anymore, which is ridiculous.

yeah in the end I phoned cotherm. spoke to a nice lady who I don't think really knew herself, said she could email me the data sheet. she did tell me setting 4 is 55c so ive set them at that, don't want the tank scaling up and any higher is bloody hot.

 

[Worcester]

However you need to go up to 60° at least once a week for an hour to destroy any legionella bacteria, they just luuuv 50° (the bottom of the tank even when 55° at the immersion.)

 

[cypher007]

However you need to go up to 60° at least once a week for an hour to destroy any legionella bacteria, they just luuuv 50° (the bottom of the tank even when 55° at the immersion.)

I thought legionella wasn't an issue in a sealed system running off chlorinated water? if it is the plumber had the stats set at about 50c on the immersions and I think the cylinder stat was on 55c.

 

[Worcester]

Legionella is always an issue with stored "warm" water, though the Building Regs don't specifically apply to an owner occupied house (landlords / rented is different depending upon interpretation)

Best practice is a different matter there is a lengthy discussion here specifically related to renewables Legionares, Solar PV water heating, Solar Thermal Water heating - Domestic | Electricians Forums

The interesting one is probably this one from WRAS: New Page 2

The standards that our installations comply with all have a requirement like "Incorporate a means to control bacterial growth (including Legionella bacteria) in domestic hot water" and point to L8

As such all our installations have specific legionella controls built in to them, and the customer is advised accordingly.

See also:
Legionnaires' disease. The control of legionella bacteria in water systems
Legionnaires' disease - Technical guidance

So should you - well we would, even if we didn't have to, it's simple enough to do and none of the energy is wasted.