Flow Temp Rising Too Quickly - Fix?

[John Smith Esq.]

Hello,

Worcester Greenstar 25i combi.

Flow temp set to 53C. It rises above this when central heating is on, by up to 5C and the boiler has registered D4 341 error (temp rising too fast).

I've run the air purge mode and it is now in auto for this. Still happening.

Boiler is in eco mode, is this relevant?

Pump head setting is on the lowest possible, should I increase it a bit? Could this be contributing to the poor circulation that can cause this problem?

Power rating is set to 9.1KW.

House is a 3 bed bungalow.

Thanks

 

[cross thread]

Try the pump speed first

 

[John Smith Esq.]

Try the pump speed first

Increase pump head setting?

I've put it from 1 to 2 (out of 4), same thing happening: Flow temperature overshooting.

 

[dilalio]

How is it on HW?

 

[John Smith Esq.]

How is it on HW?

Good question, I've never looked at this before.

It is a combi and I have the tap water temperature set to 44C. I just ran the hot tap in the bathroom and the boiler went up to 58C and then settled down to 53C as hot tap was running.

 

[Johntheo5]

Hello,

Worcester Greenstar 25i combi.

Flow temp set to 53C. It rises above this when central heating is on, by up to 5C and the boiler has registered D4 341 error (temp rising too fast).

I've run the air purge mode and it is now in auto for this. Still happening.

Boiler is in eco mode, is this relevant?

Pump head setting is on the lowest possible, should I increase it a bit? Could this be contributing to the poor circulation that can cause this problem?

Power rating is set to 9.1KW.

House is a 3 bed bungalow.

Thanks

Have got motorised zone valve(s) on the CH?, if so, when energised open, pull on the manual lever, there should be no resistance and the lever should be loose and floppy.
If a ABV is installed, check its indexed setting, should be ~ 0.3/0.4.

Set the flowtemp to say 70C (temporarily) and increase the pump to its max setting, see what happens.

 

[John Smith Esq.]

Have got motorised zone valve(s) on the CH?, if so, when energised open, pull on the manual lever, there should be no resistance and the lever should be loose and floppy.
If a ABV is installed, check its indexed setting, should be ~ 0.3/0.4.

Set the flowtemp to say 70C (temporarily) and increase the pump to its max setting, see what happens.

Where would I find these things?

 

[Johntheo5]

THe ABV might be close to the boiler, and might have a red cap, the two port could be anywhere but possibly clse to the boiler as well.

 

[John Smith Esq.]

No, those are not present. I do have one of these and I see it might need something doing with it? Relevant to the problem?

 

[dilalio]

Good question, I've never looked at this before.

Are you new to the property and trying heating on for the first time?

It is a combi and I have the tap water temperature set to 44C. I just ran the hot tap in the bathroom and the boiler went up to 58C and then settled down to 53C as hot tap was running.

Sounds fine. Did you leave the tap running for a good few minutes?

If this is a new system to you, and you've never had the CH on before, check the following...

Make sure any isolation valves below boiler are open.
Check there are no other closed lever valves on the system.
If there's a magnetic filter, with valves, that they are not closed.
All rads are ON.

If the above is confirmed/dismissed then would be...

Restriction, weak pump, air or a combination.

 

[dilalio]

No, those are not present. I do have one of these and I see it might need something doing with it? Relevant to the problem?

Lol. You posted that while I was writing!
Those valves appear to be open (on the filter) but can sometimes just spin on the spindle...doesn't look like it though.
Try bleeding it, see if you get any air.

 

[dilalio]

Increase pump head setting?

I've put it from 1 to 2 (out of 4), same thing happening: Flow temperature overshooting.

try pump on 4 for a bit, see if it shifts any air.
Check / bleed rads.

 

[John Smith Esq.]

Thanks for the responses.

I am not new to the property. All radiators are on and working fine with TRVs. I bled them all yesterday and no air came out of them.

However, I just bled that filter thing and some air came out. Not loads but some. The valves there are open - presumably would have to be for heating system to work.

I'll keep an eye on it now, as it has just come back on. Could it be that this filter needs emptying, it appears to be towards the end of the gauge. Or is this not relevant to the issue?

I have the air purge mode set to auto, so presumably that is now purging air on a periodic basis. I ran air purge mode ON yesterday a couple of times, about five minutes each time. Could run it for longer?

 

[Johntheo5]

No, those are not present. I do have one of these and I see it might need something doing with it? Relevant to the problem?

Is the arrow on the Filter pointing in the direction of the flow??, can be up or down.

 

[John Smith Esq.]

Is the arrow on the Filter pointing in the direction of the flow??, can be up or down.

Yes, it is on the return pipe and pointing down.