Solar Pump Failure ? Help

John.G

Yes, of course, you will have to replace your pump with a like for like if you want to stay running on your variable speed output relay R1, I only suggested that above in my case because I only have a on/off signal, if my pump packed up, I could utilise the smart pump running in fixed speed mode and I have a "spare" Yonos Pico somewhere. (I have 2XFlat Plates+150 litre cylinder)
Also, I'd be a bit concerned re your R1 output as its not driving the pump now, I know the pump is noisy but one would have thought that it would still be driven by that output.

If you think you will be waiting a while for repairs/refurbishment and you are feeling a bit adventurous you might consider pumping up the E.vessel to 2.5 bar (as long as the liquid end pressure matches it) this will push another litre or so of liquid into the system and might give you a bit of solar water heating but will also entail changing over the wiring to power relay R2 to drive the pump in fixed speed pump mode for now.
An how, let us know how you get on.

garyh3

Thanks John

I going to order this (below) as its a like for like (and if the pump is ok then I have a spare). Im also concerned that my control box might be faulty as its not driving the pump.

Thanks again for your advice

https://www.ebay.co.uk/itm/CENTRAL-HEATING-CIRCULATOR-PUMP-IBO-25-60-180-REPLACES-GRUNDFOS-MYSON-WILO/114123966218?hash=item1a9251870a:g:maUAAOSwunNeL0Vc

garyh3

dathi wrote: »

if you check the bottom of the tubes if the silver has turned white the vacuum has blown was a guy on adverts selling them a while ago

Looking at mine through Binoculars there seems to be a plastic cap on the bottom of then so it impossible to tell

garyh3

Can Anyone tell me how I can I get the cables out of R1 and R2. I want to test the unit by switching R1 with R2. I can then manually switch on R1 or R2 in Manual mode. Just want to make sure that R1 is not faulty if it can switch on the Over heat pump.

Im not failure with that connection block, so just some advice on how to get the L & N R1 and L & N R2 out of the blocks.

dathi

they are spring clips the little hole behind each wire opens it make sure the electricity is turned off to the controller as that's 230v

garyh3

Ok I then moved the R1 onto R2 and R2 onto R1

Bad news was that R1 didnt turn over heat pump on so it seems the controller not switching the pump on ???

When I switched the cables back R2 turned the over heat pump on.

Anyone have any ideas if it could be a fuse issue or anything to look for on the circuit board. Ive looked and cannot see anything that looks burnt or broken

Anyone any good at electronics ?

John.G

Where/what is this over heat pump? and can you just remove the cable from it and install it in the solar circ pump and see if it drives it.?, I presume you have done the same with the R1 phase and neutral and connected it to this over heat pump which doesn't turn??

When you swapped R1 & R2, did you swap the neutrals as well?, don't know if this would make any difference or not, especially to R1.

garyh3

John.G wrote: »

Where/what is this over heat pump? and can you just remove the cable from it and install it in the solar circ pump and see if it drives it.?, I presume you have done the same with the R1 phase and neutral and connected it to this over heat pump which doesn't turn??

When you swapped R1 & R2, did you swap the neutrals as well?, don't know if this would make any difference or not, especially to R1.

Hi John

Thats what I did. Both Live and Neutrol moved.

The overheat is the 2nd pump that kicks in when the tank get too hot and bleeds heat out of the system.

Gary

John.G

Interesting, some systems use R2+3 way diverter valve+dump rad, other systems use R2+ existing CH system (with boiler inhibited) to do this. (maybe your system?)

As a matter of interest, can you use R2 to start/stop your solar circ pump, (like my system) and bump up your EV pressure a bit which might keep you going for awhile until you decide on your course of action.

garyh3

The 2nd pump is just a bleed to the rads.... Company was Solar Creations, part of Allied Solar they folded about a year after the system was put in. So no support .....

I think the system probably needs a complete MOT . The tubes need to be checked so does the pump and the control unit.

Now that Ive played around with the system there's not a lot too it. Solar collector, Pump, control unit.

There are 72 tubes on 3 rails on the roof bit overkill now if I can get more efficient tubes just probable need to replace 20 tubes to get the same heat output.

garyh3

Ok Replaced the Sorel TDC 3 with a new Navitron MTDCv5, (same box)as I could not get a TDC 3 as its obsolete.

I set it option 25 at the moment solar with cooling ?? as that gives me S1 S2 S3 and a pic is similar

Has anyone done the change ? What Program Selection do you use?

TDC 3 option 2 - Sol & Thermostat currently set.
MTDC option ? 10 Solar with Thermostat or (25 Solar with cooling ?)

Option 10 I dont get the R2?

Anyone done this change ?

I have a standard Grunfos Pump 3 speed is that a PWM or a 0-10v ? I presume a PWM

Any help appreciate

Oh and the pump works with R1 on Manual so the TDM was faulty. Pump Seems to work but were still Air locked so thats next as well as putting an internal air bleed in the attic (just waiting for parts for that air bleed)

asheda99

Hi @garyh3. I've just encountered the same issue you posted back in may 2020. Did you find a resolution?

My TDC3 is on its last legs, i replaced the capacitor but I don't trust it to not fail any day. so I bought the MTDC v5. hoping its a straight swap.

my TDC3 was set to option 2 - Sol & Thermostat

MTDC - Solar with thermostat did not pick up the second Relay. so I also chose Option 25 for now but it doesn't feel right to me.

I think maybe I need to dig down deeper into the setting to enable the R2?

asheda99

FYI if anyone ever comes across this...

I just emailed sorel support for an answer:

 

First of all, it looks like Programme 10 is correct, and the connections should also be the same (see pictures below for comparison).

Then you need to go into the menu:

4.Settings > 4.19 Thermostat > 4.19.1 Th T set (set to 50 by default)

                                                    > 4.19.2 Th hysteresis (set to 10 by default)

                                                    > 4.19.3 Thermostat – select which sensor to use – I have it at „S3 storage top“

 

I’ve made a video of how I have it set up here in the simulation. but cannot share link here

garyh3

Hi asheda99

Sorry just seen your post - I purchased a Sorel MTDC unit - I think I used 25 Solar with Cooling 3 which picks up the 2nd Relay fine.(used for the 2nd pump to pump the heat away.

10 on MTDC is solar with Thermostat what solution do you have solar with 2 pumps ?

And then I dont have Setting 4 on mine

asheda99

Hey Garyh3, thanks for the reply. I emailed the Sorel support but the information they gave me was not helpful :)

I still have the same issue using option 10 using the MTDC.

I do have 2 pumps, one for solar and one for when cylinder is too hot to pump to expansion tank (I think)

I'll give your suggestion a go: 25 Solar with Cooling 3 

I had to wait a few days to retry, I managed to blow the fuse on the MTDC :)

thanks