Glow-worm Ultracom 30CXi water temp fluctuating

mpg · 16 Jul 2011

Hiya folks.

I've just replaced the cartridge in my Mira 415 shower as the temp was beginning to fluctuate... And its still doing it.

I've checked the boiler and the pressure was a little low so upped to 1.2bar.
Was @ .8.

What I noticed was that the flame icons whilst the shower was running at hottest. Were going 2-3-4-5-2-3-4-5-2-3-4-5. At about the same frequency as it feels like the shower is running hot and cooler. NOT cold.

Any Ideas
Cheers
Matt

Agile · 17 Jul 2011

The plate heat exchanger in the boiler may be blocked.

But first turn down the water temp control on the boiler towards minimum.

Turn shower to nearly maximum heat setting. Then see how it is.

Next clean out shower holes with a pin or with acid.

Then see how it is.

As a last resort turn a hot tap half on and see what difference that makes to the shower.

Tony

mpg · 17 Jul 2011

Thanks Tony,

The showerhead was cleaned today. its fairly hard water round here. So limescale is a problem.

I'll try turning down the water temp in the morning. Its set to 70c now.

Will report back

Agile · 17 Jul 2011

The boiler should not even go up to 70 C. Set it to about 48 C

Tony

DP · 17 Jul 2011

Have looked at the manual for your boiler. Would suggest 70 degree C is the correct temperature indication.

Can you run, say the bath tap and post your findings?

Agile · 17 Jul 2011

Why 70 C for hot water?

mickyg · 17 Jul 2011

whats the temperature like at other taps??

DP · 17 Jul 2011

Look at the manual Tony. I never said 70 at the tap

Agile · 17 Jul 2011

The user guide says the DHW is supplied set to 40 C but can be increased to a maximum of 62 C.

Where does 70 C come into it?

DP · 17 Jul 2011

The burner size is indicated by digits 1 to 5 and primary is neumerical display. OP did say it reads 70 degrees.

mpg · 18 Jul 2011

Sorry guys OP may have been wrong.

Although It had the tap symbol and actually read 68deg. I have now turned down to 50 deg and it gave a eco symbol next to it.

Been away so have not had time to check it but will check again today.

Flame symbols seem to be a little more stable though.

mpg · 19 Jul 2011

Ok I have turned the HW down to the Min which is 40 Deg and its still fluctuating. Shower and kitchen sink. Both within approx 3 foot of boiler.

Any Ideas

Beerlover · 19 Jul 2011

Agile said:
The plate heat exchanger in the boiler may be blocked.

Tony

You had the correct advice, right at the start.

mpg · 19 Jul 2011

Ok so where do I strike it with a hammer and how big a hammer do I need.

Beerlover · 19 Jul 2011

You sound like a boiler engineer already.

Search the forums for' how to clean a plate heatexchanger' and I'll try and find a bit more info in the meantime.

diynot

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Glow-worm Ultracom 30CXi water temp fluctuating

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