BoilerMate 2000 No hot water in the mornings when boiler turned on, HW pump runs continously when up to temp.

I have a Boilermate 2000 with Micron 50ff boiler. I switch the Micron boiler off at night, and typically there is hot water available from the Boilermate 2000 store as soon as I turn it on in the morning, or at the very least within 5 mins. In the past week or so, there has been no hot water for 90 mins or so, and when hot water is delivered the pump remains on continuously for the rest of the day.
No problems with central heating, it comes on immediately in the morning.

Can anyone advise before I go ahead with a costly repair.

Many thanks

Ben

Hi I am not sure what benefits switching the boiler off at night might bring but there you go.

In respect of your issue it would probably be a good idea to look at the main control board in the Boilermate to see what the various indicators are showing.

For example is the main display showing anything normally it would say -ON, if it has nothing showing or random dots there is a problem with the pcb. Also using SW2 (bottom of the 2 small push buttons next to the display) you can check the various temperatures to see if they are what they should be, see page 35 in the manual in this link: http://www.gledhill-spares.net/documents/bm2000-iss10.pdf

You can also have a look at this video which gives an idea of how the system works: https://www.youtube.com/watch?v=OP5-i_vi1Pw&t=410s

This one shows typical symptoms associated with a board going faulty: https://www.youtube.com/watch?v=W3wmeMnvgns&t=5s

Hope this helps. Murray

Thanks Murray.

I turn the boiler off as the boiler and then the pump (before the fault) would sometimes kick in in the night and the Boilermate is next to my bedroom and it'd wake me (super sensitive sleeper).

The LED "On" is on, and the bottom two LEDS come on too. DHW bar on the display comes on when the system is up to temp and hot water taps open, but the hot water pump remains on continuously afterwards, and doesn't cut out after 3 mins as it apparently should.

Will check temps first thing with SW2 tomorrow morning when I switch boiler on.

Checked this morning when I first turned the boiler on, temp was 46c and 47c for bottom and top sensors. Historically, even when turning off boiler overnight, I've been able to have a long hot shower within a few minutes or turning it on.  I've just rechecked after 30 mins, and the temp has only risen to 60c so far. Rechecked after another 20mins. Temp is now 75 and 74 on top an bottom sensors respectively, but showing 66 for the store. Boiler has done firing. If I open hot water tap, the DHW pump doesn't kick in and bottom sensor and store plummet to 27c and 33c respectively.

With the hot tap running and the temperatures you describe the DHW pump should be running flat out to try to get the plate heat exchanger temp into the 40 degrees area. There is no LED for the DHW pump as it is speed controlled rather than off or on but is the bottom dash next to ON appearing? You mention that with the hot tap on the store temp plummets as well which should trigger the boiler and boiler pump to kick in. It might well be that the GT155 pcb is starting to act up. You would expect the store temp to slowly drop as the DHW pump sends the store water through the plate heat exchanger and then for the boiler to kick in once it gets below 60 to replenish the store.

Bottom dash next to the ON does come on when hot water tap is open, but the DHW pump isn't kicking in. Temps before I opened tap, were 76 and 74 top and bottom, 68 store.

OK looks like either the pump is jammed or broken or the pcb has stopped providing an output to it or another HW on input is missing, time clock etc.. If you have a voltmeter you can investigate I guess. The pcb does produce strange voltages on the DHW output because as I mentioned previously the output is modulated to control the speed of the pump. There is a connection diagram in the manual. Regards Murray

Super. Thanks/