Finding Alternative for Grundfos Wiring Centre? (PumpPlan Reward :o£)

[CharlieMUK]

Hi - first post (be gentle)

I have a condensing boiler heating system that runs through a Grundfos PumpPlan Dual Pump (http://www.gasapplianceguide.co.uk/pumpplan.htm). Unfortunately, the Wiring Centre that controls it has gone bang and I can't find another anywhere to swap over.

The PumpPlan appears to have gone out of production in 2015 (ish) and I can't find any stock anywhere - the pump and control centre appeared to come as a set - I would gladly buy the pair and just use the control centre if anyone knows where I can get the set? I have googled my heart out.

I can find lots of heating wiring centres that look to control standard one pump layouts or two vales - but not dual pumps like I have.

I was wondering how hard it would be to find another wiring centre that would do the same *or* even how hard it would be to recreate what the Grundfos controller does - ie can I make my own? *or* if there is another dual pump config like the Grundfos that i could buy with its own control centre.

As you can see from the attached wiring diagram the Grundfos system has inputs for a HW Pump + CH Pump. All other wiring centres I can find have connections for 1 pump only.

(I think) My only OTHER option is to replace the single Pump Plan pump with two single standalone pumps, which will require new pumps (cost) + rerouting of pipes (cost) and heating engineer (more cost).

As such (and apologies if this breaches any community guidelines) I am happy to offer a reward of £100 to anyone that can find a workable solution, replacement or simple alternative.

There.... gauntlet set ;o)

PS - happy to give more details or pics

 

[CharlieMUK]

I did find the following site that gave some hope (http://www.the50plus.co.uk/tech_support/CH_wiring/smc.gif) < if you can see through the awful black GIF < but again I cant find the "wiring centre relay box - part number 379 575" it shows.

 

[fixitflav]

Hi - first post (be gentle)

I have a condensing boiler heating system that runs through a Grundfos PumpPlan Dual Pump (http://www.gasapplianceguide.co.uk/pumpplan.htm). Unfortunately, the Wiring Centre that controls it has gone bang and I can't find another anywhere to swap over.

The PumpPlan appears to have gone out of production in 2015 (ish) and I can't find any stock anywhere - the pump and control centre appeared to come as a set - I would gladly buy the pair and just use the control centre if anyone knows where I can get the set? I have googled my heart out.

I can find lots of heating wiring centres that look to control standard one pump layouts or two vales - but not dual pumps like I have.

I was wondering how hard it would be to find another wiring centre that would do the same *or* even how hard it would be to recreate what the Grundfos controller does - ie can I make my own? *or* if there is another dual pump config like the Grundfos that i could buy with its own control centre.

As you can see from the attached wiring diagram the Grundfos system has inputs for a HW Pump + CH Pump. All other wiring centres I can find have connections for 1 pump only.

(I think) My only OTHER option is to replace the single Pump Plan pump with two single standalone pumps, which will require new pumps (cost) + rerouting of pipes (cost) and heating engineer (more cost).

As such (and apologies if this breaches any community guidelines) I am happy to offer a reward of £100 to anyone that can find a workable solution, replacement or simple alternative.

There.... gauntlet set ;o)

PS - happy to give more details or pics

Without knowing just what the Pump Plan does, why not connect the stats direct to the respective pump? If only as a temporary fix while you source a permanent solution. You can't just common the outputs from the 2 stats to supply the boiler, as both pumps would start when either stat calls, but adding 2 relays solves that. I can post a rough sketch if you want.

 

[CharlieMUK]

Hi and thanks - you will have to forgive my ignorance - "Stats"?

Rough Sketch - yes please - if you are OK to do so... I wonder then if it would be possible to recreate the circuit operation to work around the blown board??

 

[fixitflav]

Hi and thanks - you will have to forgive my ignorance - "Stats"?

Rough Sketch - yes please - if you are OK to do so... I wonder then if it would be possible to recreate the circuit operation to work around the blown board??

Short for thermostats. I'll post a sketch in a bit.

 

[heatservice]

If Grundfos no longer make it I would consider replacing it with a 3 port or 2 zone valves.

 

[fixitflav]

Hi and thanks - you will have to forgive my ignorance - "Stats"?

Rough Sketch - yes please - if you are OK to do so... I wonder then if it would be possible to recreate the circuit operation to work around the blown board??

Sketch attached. Excuse the blob on one of the relays, I drew it slightly wrong and Tippexed it!

If you want to add a Frost-stat it would need a 3rd relay, but I wouldn't bother, specially if it's temporary.

 

[picasso]

And if the boiler needs pump overrun ? might be a good idea to ask what boiler the op has .

 

[fixitflav]

And if the boiler needs pump overrun ? might be a good idea to ask what boiler the op has .

If it does, he could use the pump overrun contact on the boiler, as shown on the Grundfos diagram. Connected to the CH pump.

 

[Iankw]

I also have a pump plan. Great idea pity grundfoss didn't support it better. However, I had a problem also with the wiring centre. The fix was relatively easy depending on your skil level and equipment available. The pump plan pcb is pretty basic with not much to go wrong actually. Assuming the fuse is intact and you are not getting hot water or heating control or both. It almost certainly is the orange relay that is at fault. The component is marked with the model number. In my case RT424730 cost £5 or £6 or thereabouts. If you have a desoldering pump or desoldering wire and can use a soldering iron replacing the component is not too difficult. Otherwise find someone who is into electronics and they can do it for you. At such a low cost it is worth a try. I've just added a nest thermostat to my pump plan and it's running great.

 

[ianmcd]

I also have a pump plan. Great idea pity grundfoss didn't support it better. However, I had a problem also with the wiring centre. The fix was relatively easy depending on your skil level and equipment available. The pump plan pcb is pretty basic with not much to go wrong actually. Assuming the fuse is intact and you are not getting hot water or heating control or both. It almost certainly is the orange relay that is at fault. The component is marked with the model number. In my case RT424730 cost £5 or £6 or thereabouts. If you have a desoldering pump or desoldering wire and can use a soldering iron replacing the component is not too difficult. Otherwise find someone who is into electronics and they can do it for you. At such a low cost it is worth a try. I've just added a nest thermostat to my pump plan and it's running great.

you have just commented on a post that is over 2 years old, I think it might be sorted by now

 

[Iankw]

His problem might be but I thought it might be usefull for someone else searching for the same problem in the same way as I was searching help. Just trying to help.

 

[steve 53 roberts]

Hi Ian don't suppose you could give me the wiring diagram you used to add a nest thermostat to the Grundfos pump plan as this is something i am considering adding to mine

 

[Iankw]

Hi I got a bit confused with the COM terminology thinking it was the same as Neutral so I got a mate to sort it for me. However, I am sending some pics which I hope will help and an explanation of how mine is wired up.
From Grundfoss wiring center the bottom right vertical connector block L and N go to nest L and N. There are 2 link wires in the nest from L to 2 and another from 2 to 5.
The Grundfoss wiring centre HW goes to Nest 6 and the CH from the wiring centre goes to Nest 3. This works for me perfectly. However the usual disclaimer applies that I accept no responsibility for your system. Hope this helps.