Please help !! looks like my adventure with Grundfos ALPHA2 L 15-60 130 gone wrong!

sujsuj

@Bendy House - things are getting more clearer now.. Could you clarify on this lever mentioned below..?? where is this lever? how can I move that lever? Tahnks.

If you manually move either of these valves to their open position using the lever I mentioned, then they should 'trigger' the boiler and pump to come on, even if the programmer says 'OFF'. But, the valve needs to make a click at the end of the lever travel for this to happen.

Please note at the moment whatever I do on thermostat makes no difference to boiler no tick/click sound. Thanks

FreeBear

Bendy_House said: - let's face it - the programmer needs replacing anyway, so no harm in trying this.

If you are going to the expense of replacing the timer, you may as well replace the thermostat as well. Get a programmable thermostat that allows you to have different temperatures set for discrete time slots throughout the day/week. You could save 15-20% on your heating costs (more likely around 5%).

Bendy_House

sujsuj said:

@Bendy House - things are getting more clearer now.. Could you clarify on this lever mentioned below..?? where is this lever? how can I move that lever? Tahnks.

If you manually move either of these valves to their open position using the lever I mentioned, then they should 'trigger' the boiler and pump to come on, even if the programmer says 'OFF'. But, the valve needs to make a click at the end of the lever travel for this to happen.

Please note at the moment whatever I do on thermostat makes no difference to boiler no tick/click sound. Thanks

Could you take a close-up pic, or otherwise let us know the make and model or the motorized valve, please?

sujsuj

Thanks very much.
On closer look its a DANFOSS Type HPA2 one. I can see AUTO and MAN modes and currently lever as expected in AUTO mode. I can see Lever on top can be moved to MAN mode. Please see photos.

There are 2 valves connected not sure what each one is doing as both seems to be connected to 2 branches of same pipe from water heater..? One closer to water heater and another away in another branch..

Please let me know what steps to be taken here now? thanks

Bendy_House

Valves B and C are identical items.
They are supplied by the hot flow from the boiler. They open up to allow that flow as required - B ( the higher up one) serves the hot water cylinder, and C the central heating.

The sequence of operation is: (let's choose the DHW side as an example), the Programmer says "l'm timed to come on now to heat up the hot water cylinder - 'click'!".

This sends the 'on' power to the cylinder thermostat.

The 'stat says "Yup, the water in the cylinder is colder than my setting, so I am 'on'". The 'stat sends this 'on' power to the motorised valve B, and this whirrrrs open.

At the end of the motorized valve's travel, it trips a microswitch and goes 'click'.

This sends the 'on' power to the boiler and the pump which only then come on.

What I'm hoping you can try, then, is to by-pass everything except the motorised valve, but it has to go 'click' for this to work. If it goes click, then it'll send the 'on' signal to the boiler and pump regardless of everything else.

Ok, what I'd suggest is: turn off the boiler power supply switch. Now move that lever from 'auto' to 'manual'. It'll be stiff but hopefully smooth - don't snatch at it, but press it steadily all the way across to the far manual end - it'll take you 2 or 3 seconds, and will whirr as you do this. If you release it at any point, it'll just return to 'auto' under spring pressure. 

Ok, the important bit - when it approaches/reaches the 'manual' end, it needs to make an obvious 'click' from the microswitch I mentioned, and only one click! Sometimes they click as you overshoot the switch point, but then - as you hold the lever tight against the manual end - the mechanism resettles and it quickly goes 'click' again. That means it's gone off again, which is no good!

So, power off, and have a play. Push to VERY far end and HOLD. Listen for the click. Does it click just once as you reach the end? Or does it not click at all? Or does it click and then click again a second later?

Only the first scenario is really any use to us.

Ok, now you've had a play, turn the power back on and repeat.

sujsuj

Thanks Bendy_House.

I switched off power and moved lever to manual and heard sound, then switched boiler on, 
Now, Grundfos is working (glowing green and can change to different pressure setting) and also boiler switched On. I can see pipes are hesting up..

Does this proves anything..? whats the next step..?

molerat

It proves the Danfoss timer is not working.

The timer does not switch on the pump, it merely tells the valves to open and, as you have done manually, the microswitch in the valve turns on the pump and boiler.

You can leave the hot water one at manual for a while and you will get a tank of hot water.  It will likely get hotter than normal as it will be controlled by the boiler water temperature rather than the thermostat on the tank.

sujsuj

Thanks, its not just Danfos controller itself is no more working right..?  not just the display
Previously only display was faulty but timer used to work as per schedule .

is there a way I can put valve back to AUTO and try that schedule again..? Thanks.

molerat

Just pull the lever gently out of its detent notch and the valve will go back to auto, you will hear it whirr as it runs back.

You could try and reset the Danfoss timer.  Open the flap and on the right there is a little oblong button marked R/S.  Get a pencil or cocktail stick and gently poke it.  The 2 red lights should flash once.  That will reset the electronics but retain all settings.  Screen off, lights on can be caused by a power surge.

Bendy_House

Blimey, sujsuj, I didn't expect that to work!

As Molerat says, your programmer is kaput. Good idea to try resetting it, but why you are trying to hold on to a PoS that doesn't even have a functioning display, beats me  

The 715 has a 'standard' backplate. That means that lots of other programmers will clip straight on to it. If you are happy with such a basic setup, then the Drayton Lifestyle 722 is pretty much the standard programmer these days, and should fit straight on. You can pick these up from around £50 if you look hard enough.

A FAR superior option would be a 2-channel Hive. Yes, I know they cost more, but - at around £100 - not that much more, and actually the Danfoss 715 costs a LOT more than that! You can pick up the Hive for much less on eBay if you bide your time.

A Hive is a different order of controllability altogether. Add a Hub, and programming it is stupidly easy, and fully overrideable by phone App, and it tells you your previous usage.

Although fitting a Hive is largely a plug-in job, you will need a sparky to disconnect your current room stat from the wiring centre. The old stat can be removed, and the Hive mounted on the wall in its place. Or moved elsewhere - it's wireless.

So, choose a 2-channel programmer that uses a standard backplate (and that includes the Hive).

After trying the rest :-)