S53 on Glow Worm Easicom 28

[rsg444]

Hi there, I've been going through the forum for the past few weeks and have read every single S53 thread on here.

My boiler, an Easicom 28, when it starts up heats the radiators very slowly and takes ages to reach the target flow temperature. I discovered that it was throwing up a code S53.

I have balanced the system as suggested in the other threads, is there any possibility that the main heat exchanger can cause this if it is blocked?

I had an issue with my hot water last year where the hot water kept fluctuating, the heat exchanger plate was clogged with muck, it was cleaned with acid and this sorted out the issue....for 3 months until it happened again. This time I had a new plate installed by Vaillant. When I described the symptoms to him about the slow heating he suggested that the main heat exchanger was likely to be clogged with the same stuff as what was in the heat exchanger plate. He changed the pump to a brand new but I've still had the same issue and it now takes even long to heat up the radiators.

I had a powerflush done last year and very little stuff came out, I have inhibitor in the system and a magnaclean (which when I checked today, a year after the powerflush did have some sludge over it).

Any advice, comments would be appreciated.

 

[muggles]

It's virtually impossible to powerflush those heat exchangers - they're made up of a number of small tubes running between two manifolds. If one tube gets blocked, powerflushing just sends water round the ones that aren't blocked, because water will take the path of least resistance. Only a new heat exchanger (or new boiler) will sort it

 

[rsg444]

Thanks muggles. I've been experimenting further, I don't think it is the heat exchanger as the boiler is producing some serious heat when I touch the outbound pipe from the boiler, however the one that is going into the magnetic cleaner is cold - it is this differential that is causing the boiler to go into limp mode...I think.

Now I can't figure out what part of my heating system is causing this. Today, I turned off all the radiators/towel rails and kept the one in my kids' bedroom open, it heated up almost instantly, no S53 code, so I then opened the next bedroom one, this heated up instantly, then the next, I worked my way downstairs and the boiler was fine, no S53 error. This to be says that the boiler is fine, it is my heating system - maybe poor design from previous owner or sludge. I bled a radiator, the water was pretty much clear, I cleaned out the magnetic cleaner, there was some crud but nothing major. I'm at a loss - I just want to house to heat up to a reasonable temperature within the hour - right now I can have it on for 3 to 4 hours and it'll just about hit 19 degrees.

I've left the towel rail in my bathroom off as I read somewhere they can cause S53 issues - is this right?

 

[ScottishGasMan]

No. S53 is simply there is not enough water flowing through the boiler to allow it to run at full rate.

Firstly, how many radiators are you heating? the boiler will likley have not been set for the number of radiators you have or more accurately for the flow rate your heating system will take, look at the manual about accessing the D - Codes. In the D-Codes, D0 (zero) is the "Range Rating" mechanisim for the heating output. it will probably be at full. Depending on the flow you have, typically half that figure will do. set it to 15. then once its saved the new parameter, turn the power off and back on, and give the heating a go again.

5 to 10 min the boiler will run in low rate, then up to 15kw, rather than the max rate, you should find a much more steady heat now

 

[rsg444]

ScottishGasMan, I'm heating 8 radiators (7 of which are type 22, 1 is a type 11) plus 2 towel rails. I've been researching this whole heating a house stuff for over a month now due to this S53 issue and so calculated the amount of BTUs I need per room using an online BTU calculator based on room sizes, I added it all together, converted it to kW and came up with a value of just under 10kW - taking into consideration heat loss (I have solid brick walls) I reckon the kW needed to heat my home is probably around 12kW - does that sound right?

Anyway, I took your advice, finally found the manual and discovered the d0 menu - d0 was set to 24, so I have scaled it down to 15 and wow! the house actually heated up properly and all the radiators were nice and hot for the first time since I can remember - there was no S53 error.

Tomorrow I'll test it again with a cold start and fingers crossed it'll work again - the d40 this evening was 65 and d41 was 46 - does that sound right?

Thank you so much for your assistance ScottishGasMan, you have saved me a lot of money as I was very close to buying a new boiler (as this is what the Vaillant engineer said I should do if the problem persisted - why he didn't just lower the heating power output is beyond me.

From this, it suggests that most boilers are running with way too much power and perhaps, a lot of people are buying boilers that are oversized for their needs (that's of course if I've understood these BTU and kW calculations correctly.

 

[ScottishGasMan]

No, your quite right, many boilers are massively oversized for their actual needs. In the case of combis, they have to be to provide instant hot water, the difference between a 30kw and 24kw combi is pretty noticable in terms of hot water use, but both will be miles over what a standard house needs for heating.

65/46 is about perfect for the D40/41 numbers, Your aiming for about 20degrees of difference when the heatings heating up (the difference between them will narrow significantly when the systems up to full temp)

I've seen this issue and altered the output to suit many times and never had any bother with them after a little setting up so I expect it will work fine for you from here.

 

[rsg444]

Thank you! Will post an update in the next few days with how things progressed.

 

[rsg444]

So a quick update as to the S53 situation, after following ScottishGasMan's advice, I lowered the d.0 setting to 15kW and wow, what a difference it has made, no more S53 errors, house warms up nicely and I've noticed that the boiler hardly turns on anymore, before it was on for hours struggling to try and meet the temperature that the room thermostat was asking for.

Thanks again for your help!