Water not getting hot enough

a leak between primary & secondary circuits?

the obvious candidates are the primary stat & tank stat. A less likely cand idate might be pump failing or crudded up resulting in the boiler quickly c utting out but pump keeps running - that would cane CH output as well thoug h. Muck in the DHW cylinder exchanger is also possible. Telling us a lot mo re about the system would help.

So would using anywhere else to access this place from. Most regulars have h o h blocked.

NT

The stat on the boiler itself? If it isn't producing water at a high enough temperature, it'll never get enough heat to the HW.

Start by checking the flow temperature of the water out of the boiler (i.e. the actual pipe temp, not the indicated on the dial temp).

Basically you need to find out of this is a lack of flow temperature problem, or a controls problem / cylinder problem.

It's worth adjusting the stat knob and listen for the click of the contacts; see if the figure equates to the temperature of the cylinder under the stat.

I had the contacts on a Danfoss ACT go open circuit (sometimes!). Purchased a replacement off eBay and found that the calibration was wrong; reading 15 to 20 degrees high; another was sent without quibble and not wanting the first one back. The second one was exactly the same so called Danfoss, explained the issue and they asked me to send one for investigation. I realized I didn't need to fit the stat to test it as just held in my hand the contacts were changing over at 50 degrees; my hands are not that hot! I have left one on the cylinder set to 75; the cylinder temp is a shade under 60.

Note that calling Danfoss since they moved sales and services from Bedford to Denham needs patience - a lot of it!Only the sales number was working, the background noise was appalling and it really does take an awful long time to get an answer whereas they used to be slick.

Mike