Yet another Stuart M330N pump problem

copacetic · 29-11-2009 07:37PM #1

Have done a search and been around the web a few times, but would like the experts on heres point of view. I have one of these pumps that isn't working. Basically it's my own fault for not getting it sorted sooner. Over the last 4 years I've normally had to reset the pump once a month or two to keep it working. Over the last few weeks, I've had to do it more and more to the stage where I'd have to reset it in the morning when getting up, for the last week. The pump would then work fine as long as it was kept running. Once there was no water flowing it would cut out and the next time it was required would have to be reset again by switching off for 10s.

This morning after the reset it just started buzzing rather than come on and has been the same since. It just won't come on. I've tried all the troubleshooting steps I've seen mentioned and believe the most likely solution is a pcb replacement.

However I'm concerned about the fact that the pump 'buzzes' as if it is trying to start but is blocked somehow. i.e the pump is trying to start, so maybe the PCB ok? Has anyone who replaced a PCB in one had the same symptoms?

Are modern plant the people to deal with and can you collect parts from them, rather than wait for delivery? The pump is required to get hot water to anywhere in the apt, so its pretty urgent to get it fixed.

Joey the lips · 29-11-2009 09:27PM

Modern plant are the agents but will not deal with the pump if it was not bought in ireland. They will know by the serial number and if it has not one they wont handle it.....Lovely people.:)

Anyway it really boils down to the circuit board or flow switch. The problem is that the pumps are so cheap buying in that modern plant will of half charged you by the time you get it to them

A 330n Monsoon new in ireland will cost about 600 Euro

copacetic · 29-11-2009 09:44PM

Joey the lips wrote: »

Modern plant are the agents but will not deal with the pump if it was not bought in ireland. They will know by the serial number and if it has not one they wont handle it.....Lovely people.:)

Anyway it really boils down to the circuit board or flow switch. The problem is that the pumps are so cheap buying in that modern plant will of half charged you by the time you get it to them

A 330n Monsoon new in ireland will cost about 600 Euro

Cheers Joey, the pump came with a new apartment, so I assume it was bought in Ireland, but could
have been brought in from UK I guess. so you don't think it could be blocked somehow?

Turner have this to say in their faqs:

My pump keeps "humming", what is wrong?
This is a sign of the pump being jammed or stuck, stopping the free rotation when required. This could be as a result of infrequent use in a hard water area for instance, where the seals or other moving parts can become stuck, or alternatively this could be as a result of an electrical issue. You will probably need a qualified service engineer to sort this problem, call our Pump Assist helpline for further assistance.

but I don't see how it can be jammed since it has gradually gone funny over years and pretty sure I have soft water (D18)

I could replace the pcb myself if they will supply one, the only issue really is the very awkward position it's been put in. I'd like to rule everything else out if I could. Any ideas on how to rule out the flow switch? I've tried to rule them out with a magnet, which didn't cause the pump to come on. Anything else?

Based on previous boards threads, it's €50 or less for pcb and €150 or less for a call out and fix including pcb? Seem a lot better than €800 or so for a new pump + fitting?

From having a look at the pcb, the parts all look cheap enough, so could possibly replace them one at a time. Any ideas on what the problem generally is with the pcbs? Have seen people mention the caps and the relays.

Joey the lips · 29-11-2009 09:54PM

If your confident you can actually check if the pump is jamming by taking off the ends and seeing if its rubbing. Just make sure the water and power are isolated. You would be surprised. I have seen plumbers isolate the power but forget the water

copacetic · 29-11-2009 09:57PM

I've not really confident around plumbing, but am ok with electrics. If I seal the water valves on the pipes in to the pump and run the water out of it my using my taps, will I still get water fall from them when I take them off? I'd be worried about dropping water on the pump itself as it is pretty much installed under all the pipework..

mad m · 29-11-2009 10:00PM

I'd say if it was the PCB blown then you would get nothing at all from it not even your buzz....I was at one of these half day trouble-shooter courses Modern plant gave and dismantling a pump can be tricky, well to replace the PCB is straight forward but replacing an impellor you would want to be carefull....

Resetting a pump daily means that the stat on the pump has reached a certain temp and shuts down the pumps to protect itself. Anything over 60degrees is not good for pumps...

Like most things if your nothing doing it daily you forget things and I would need to do that half day course again....

copacetic · 30-11-2009 09:41PM

What a day! almost successful though.

So most likely problem was the pcb, bought one for €50 at lunch and fitted it with difficulty with pump in situ. Didn't solve problem! Dropped back in to modern plant on way back from lunch and got the capacitor ~ €25. Capacitor impossible to fit without taking the pump out. Just finished taking pump out, fitting capacitor and fitting pump back in.
Pump now works. Yay!

Problem though, I've somehow bumped or twisted one of the connections and now have a slow drip. It's where the flexible hose is connected to the copper pipe. I have a drip coming off the top of the connection. It seems pretty tight, i.e if I try to tighten it I feel like I'm going to twist the pipework.

Any ideas from the experts?? It doesn't look like it was soldered, is this a compression joint and if so how do I seal it? It's a really slow drip, i.e it feels like it could be left for days without filling a bowl of water. Could I seal it with plumbers paste or with solder? At least until I get someone who knows what they are doing to have a look?

cnocbui · 30-11-2009 09:59PM

I am sure Joey will know for sure, and can suitably correct me, but that looks like it is probably a compression joint with an olive in there. I would undo the joint by holding the nut on the braided hose steady and tuning the other one.

If it is an olive, just wrap some ptfe tape around the olive a few times and tighten it all back up.

Joey the lips · 30-11-2009 10:16PM

cnocbui wrote: »

I am sure Joey will know for sure, and can suitably correct me, but that looks like it is probably a compression joint with an olive in there. I would undo the joint by holding the nut on the braided hose steady and tuning the other one.

If it is an olive, just wrap some ptfe tape around the olive a few times and tighten it all back up.

I appreciate your comment but I am not that good. What I would do is I would again isolate the pump turn off the water and give the nut a light turn about 10mm should do it. I would say the olive is fine it just needs to be reseated agaist the nut. Then turn on the water and see if the leak is worse/better. I reckon it should be gone

If your not happy doing this the olive and nut might need to be redone but its been my exp that the turn would be enough.

You will have to have a spanner on the nut beside it on the gate valve to stop it turning though.

copacetic · 30-11-2009 10:29PM

Thanks again Guys, will try that Joey. Just had first shower since Saturday morning so am in great form!

As these threads seem to come up in google for people searching for solutions. I'd have two comments to make.

1) If you pump is humming but not starting, it's the capacitor or a blockage. The capacitor is easily changed if you have access. It's attached to the wires by slide on clips.

2) Otherwise, if you get nothing. The cct board is apparently the most likely problem with them. The replacement is a different design which moved the main power in much closer to the relay for the motor. Looks like a better design so I left it in. It's an easy enough job if you are confident with a little wiring. The only issue is the power in has moved 5cm or so across the board away from the entry point. So you need that much play in your wiring. You have 11 wires to move (2 for each ctrl switch, L, N and E for the power in and M and N for the motor) so you just need to be careful to mark them before you removed them or move them one at a time. They are all in terminal blocks so you only need a screwdriver.

It costs €75 for both parts, which is pretty steep for whats on them but worth it before throwing 4 or 500 away on a new pump. Have seen that this might only be a temp fix and problem may reappear requiring the pump replaced, but it's worth a go.

mad m · 30-11-2009 11:56PM

Fairplay^^

Mick1978 · 02-04-2010 08:20PM

Thanks Copacetic for all the info provided,it has helped me a lot to find out what was wrong with my pump.I have bought the parts(capacitor and PCB) and will replace them tomorrow.Fair play to you!

copacetic · 02-04-2010 08:47PM

Well best of luck with in Mick, just take in slow and by careful to turn off power etc. Mines been fine since I changed the parts. Do the capacitor first as it's the easy one to try, especially if you have access and can do it in situ.

antoinolachtnai · 03-04-2010 10:20PM

The problem with the old pcb's seemed to be that they were very sensitive to surges in the power supply. This has to do with how they step down the voltage to power the control circuit. The new PCB seems to have more specialised components that are more resilient.

The sequence for testing, if you are handy with electrics, seems to be as follows:

(note: this assumes you are comfortable working with mains voltages and know the procedures to be safe. If you are not, then you will need help from somebody handy.)

0. Check obvious stuff - that there is water, that there is power, and that the fuses haven't blown.

1. open top that covers circuit board.

2. try starting the pump motor by applying power directly to the terminals that go into the condenser and pump motor. If the pump runs, this means the problem is either with the flow sensors or the PCB. See instructions in manual for testing sensors. But it is probably the PCB.

3. Next thing seems to be the capacitor. You can try changing that. It might solve your problem. This worked for shower doctors when they came out to fix my pump. Easy enough. You might notice that the old, failed capacitor is slightly swollen.

4. If all that fails, then there is something wrong with the actual pump, i.e., it is jammed or otherwise broken. Now you are looking at dismantling the pump. I've never gotten this far so can offer no suggestions. In fairness, the pumps themselves seem very solid, it's the electrics that give problems.

Mick1978 · 06-04-2010 08:24PM

Hi all,

replaced capacitor and pcb to make sure is all ok.Sometimes there was a humming noise(capacitor problem apparently) and pump did not start other times the pump started again after being switched off for 10 seconds.After replacing them,everything seems to work fine,it's been two consecutive days since replacement took place and pump works perfect.I guess in my case the pcb replacement would have been enough but to be 100% i've replaced the capacitor too.Not easy to do as there was very little room to manouver,but if you replace wires one by one you can't go wrong.Live and neutral wires are connected at the back of the board not as it was on the previousa board,but this is explained on the leaflet you get with the pcb.Thank you guys for the help,it helped me out so save some money and learn a new experience.

copacetic · 06-04-2010 09:34PM

sweet, good work Mick.

dave 1 · 20-04-2010 10:10PM

hi can some one help me. we had a power cut and my pump stopped working. i have just replaced the pcb board and now when i connected the power i just go a buzzing sound there is no taps on at this point so i took the fuze out to stop the buzzing. should i change the capacitor?
cheers.

copacetic · 20-04-2010 10:22PM

yep

antoinolachtnai · 20-04-2010 11:04PM

Yep, sounds like it. You can always ring modern plant and ask for their advice.

Hope changing the cap works for you.

dave 1 · 21-04-2010 10:21AM

just spoke with modern plant and the guy said the pump is ceased. because it has not been run for a while. if i open the side and try and turn it manunally it might work? any idias..

cnocbui · 22-04-2010 12:07PM

I have had mine seize when it was left unused and we were off on holiday for a few weeks.

If it is a monsoon model, take a look at either end of the motor where it joins the pump sections. One end has some slots through which you can see the vanes of an integral cooling fan.

With the pump switched off, use a screwdriver or something similar to reach in and move the rotor by pressing on the fan blades.

I only had to move mine a small bit then switched it back on and all was well.

shrek008 · 11-05-2010 09:44PM

Hi, i have a stuart pump that provides water pressure for the whole house,w e had three power cuts yesterday in quick succession and the pump wont turn off since! The pump seems to be working constantly even when all taps etc are off. when taps are turned on we have great pressure as normal.Is there a danger that i will do further damage by leaving pump on?Have tried resetting by removing fuse and waiting a minute before replacing but it just keeps on pumping when i replace fuse!HELP

mad m · 11-05-2010 11:17PM

shrek008 wrote: »

Hi, i have a stuart pump that provides water pressure for the whole house,w e had three power cuts yesterday in quick succession and the pump wont turn off since! The pump seems to be working constantly even when all taps etc are off. when taps are turned on we have great pressure as normal.Is there a danger that i will do further damage by leaving pump on?Have tried resetting by removing fuse and waiting a minute before replacing but it just keeps on pumping when i replace fuse!HELP

Are you sure nothing is running like an internal overflow in your toilet. Don't leave the pump running constantly. It might burn out on you..Have you tried throwing the switch at fuse board instead of spur switch...

shrek008 · 13-05-2010 12:43AM

Thanks Mad M, threw main switch at fuse board and hey presto pump works perfectly!Thanks for the tip.

smiles290 · 19-06-2010 08:55AM

Hi, This is a great forum. I've a stuart pump that comes on and off for a couple of seconds by itself every 2 or 3 minutes. This happens without me turning on any taps. I've had it inspected by a plumber but he cant find any fault with it. Its driving me mental, especially at night time. Does anyone know what the problem might be?

Opus_One · 26-06-2010 04:09PM

Thanks for all the advice and great posts.

We have a 330n and the circuit board blew last year following a power cut/surge, was replaced with (an improved, newer model) board from Modern Plant which solved the problem fine. (Capacitor was not replaced).

Now we the pump is intermittently refusing to come on, and is buzzing from time to time. By turning on all taps / flushing toilets and/or resetting the pump at the fuse, the pump seems to come back on after a few minutes.

From all the info posted here and on other sites it would seem that I need a new capacitor, which I intend to order online and fit myself, however I can't seem to find the exact model on the Stuart Turner website. The Monsoon twin seems to be closest, but the body of my pump is green metal (like their Stuart range of pumps).

My questions if anyone can help:

1. Can anyone point me to the exact model we have in Charlesland, on the ST website or has it been replaced by a newer/different model?

2. Are all of the capacitors which can be ordered online on the ST website, the same for the Monsoon range of pumps (Capacitor 7 µF). They all appear to have the same description and price, but have different part codes?

3. I've taken the cover off the circuit box and the capacitor looks like it's just connected to two clips - is it a straightforward job to replace?

Thanks, and any tips or advice very much welcome.

copacetic · 26-06-2010 04:44PM

it's a very straightforward job if you have decent access to unclip the cap. I think the 330n has been replaced so you won't find it on the site. However I think most of the caps are the same, the best way to check you are getting the right one is to take your one out to compare it (making sure to isolate power first!)

smiles290 wrote: »

Hi, This is a great forum. I've a stuart pump that comes on and off for a couple of seconds by itself every 2 or 3 minutes. This happens without me turning on any taps. I've had it inspected by a plumber but he cant find any fault with it. Its driving me mental, especially at night time. Does anyone know what the problem might be?

You most likely have a dripping tap/toilet that is bringing down the pressure a little so the pump comes on to keep pressure up. Put tissue paper in all your sinks and against the back of toilet bowls and see does it get wet after a few minutes. It could also be a leak somewhere. Failing that it may be the pressure vessel set too high (or too low). A work around while you investigate is to put in a timer on the power to the pump so it can't come on say from 1am to 6am.

antoinolachtnai · 26-06-2010 06:12PM

For spare parts ring modern plant and see what they say.

Opus_One · 26-06-2010 06:47PM

Thanks!

emc2 · 04-07-2010 08:29PM

Hey guys,

I am having a problem with a stuart turner pump (st66). So the board blew and I replaced it but i am still having an issue with it. Now the pump stays on all the time. Anyone have any ideas what i need to do to sort it out.

copacetic · 04-07-2010 08:38PM

emc2 wrote: »

Hey guys,

I am having a problem with a stuart turner pump (st66). So the board blew and I replaced it but i am still having an issue with it. Now the pump stays on all the time. Anyone have any ideas what i need to do to sort it out.

Do you have take it out and put it back to change the board? If not and you didn't disturb the plumbing at all you probably just need to reset it at main board as mad m posted above.

Yet another Stuart M330N pump problem

Comments