Yet another Stuart M330N pump problem

copacetic

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

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

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

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

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

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

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

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

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

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

Fairplay^^

Mick1978

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

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

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

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

sweet, good work Mick.

dave 1

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

yep

antoinolachtnai

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

Hope changing the cap works for you.

dave 1

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

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

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

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

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

smiles290

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

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

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

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

Opus_One

Thanks!

emc2

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

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.

emc2

copacetic wrote: »

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.

I didn't need to remove the pump to change the board. I did try to flick the switch on the fuse board to reset it but that didn't work.

copacetic

emc2 wrote: »

I didn't need to remove the pump to change the board. I did try to flick the switch on the fuse board to reset it but that didn't work.

It's hard to say but you aren't getting pressure, check all the valves are open, and run all the taps/flush all the toilets, sounds like air somewhere

(note - electronics are my thing not plumbing..)

emc2

What I think the problem is is that it is stuck in the on position. There is a grey switch box but it's a sealed unit so I'd like some advice before I go poking about in it.

gqma0

Thanks to this thread, we now have water back. Th capacitor was humming. After opening the top, I was able to easily retrieve the capacitor. It was quite swollen and stopped buzzing. I managed to get a 8uF from my washing machine repair shop as he had no 7uF and I couldn't find any in Maplin. I've ordered one from the UK

Now, the pump is working again but the water pressure on the cold water is very weak. I've noticed that it was weak before it started failing last week but it's worse now. Do you think it's a problem on the PCB this time ? Does anyone know the fees from Modern Plant ?

Thanks again.
G

antoinolachtnai

It sounds to me like something else. Replacing the PCB is extremely unlikely to make the pump give better pressure. The motor the pump itself don't sound too good. I've a feeling you might be better splurging out for a new pump.

gqma0

antoinolachtnai wrote: »

It sounds to me like something else. Replacing the PCB is extremely unlikely to make the pump give better pressure. The motor the pump itself don't sound too good. I've a feeling you might be better splurging out for a new pump.

Thanks for the reply. It had already been replaced for the same problem 3 yrs ago but the 1st one was under warranty as we moved into a new house. How much does one of these cost ? Could the hard water be the cause of the problem as my plumber said ? Tight for money these days

Thanks
Cheers.

antoinolachtnai

I guess it could be hard water alright, but I am no expert. I would ring Stuart Turner and Modern Plant and ask them what they think.

Dismantling the pump and clearing it out might help, but I really don't know, I have never done that.

gqma0

antoinolachtnai,

Thanks for the advice. I will try dismantling the pump and clearing it out and if that doesn't work, I will contact Modern Plant.

I might give them a ring and see what kind of damage I can expect.

Will post back.

antoinolachtnai

I would actually ring them first, to ask if there's anything to watch out for and to make sure you have all the technical documentation.

gqma0

antoinolachtnai wrote: »

I would actually ring them first, to ask if there's anything to watch out for and to make sure you have all the technical documentation.

will do.
:-)

Joey the lips

Modern plant will not touch a pump ie service or repair it if you did not buy it from them. They are a stubborn crowd for this.

They know where you bought it by the serial number. Just to keep you in the loop.

gqma0

Joey the lips wrote: »

Modern plant will not touch a pump ie service or repair it if you did not buy it from them. They are a stubborn crowd for this.

They know where you bought it by the serial number. Just to keep you in the loop.

It has a Modern Plant logo on it and their phone number as well. Anyway, the low cold water pressure seems to have been temporary since it's back to Normal since yesterday. I'm not too sure why this happened but I'll keep an eye on it.

antoinolachtnai

It could have been some diet in the line that got blown out once there was a bit of pressure.

I would be surprised if shower doctors who modern plant send for service calls, wouldn't service a non MP plant. But I don't know really.

If you are able to dismantle it yourself, I can't see what mp or sd could do that you couldn't do yourself in conjunction with the ST helpline.

The Shower Doctors

Hi there
If its a Stuart Turner Pump yes we can repair it.I am not fussy where it came from as long as is not a "warranty Repair". For this you need to talk to Modern Plant. Other wise Give us a Call on 6205657.If you mention you found us on the Forum I will give You a Genuine 5% reduction off the cost of the repair.If you wish we also do in house repairs at a reduced rate.
Regards
Steve

antoinolachtnai wrote: »

It could have been some diet in the line that got blown out once there was a bit of pressure.

I would be surprised if shower doctors who modern plant send for service calls, wouldn't service a non MP plant. But I don't know really.

If you are able to dismantle it yourself, I can't see what mp or sd could do that you couldn't do yourself in conjunction with the ST helpline.

The Shower Doctors

Hi there
did You ever get that pump Sorted?
Cheer
Steve

gqma0 wrote: »

antoinolachtnai,

Thanks for the advice. I will try dismantling the pump and clearing it out and if that doesn't work, I will contact Modern Plant.

I might give them a ring and see what kind of damage I can expect.

Will post back.

gqma0

The Shower Doctors wrote: »

Hi there
did You ever get that pump Sorted?
Cheer
Steve

Hi Steve,

I rang Shower doctors on Friday but the lady told me that it could take 2, 3 days for a service callout engineer and the price was quite discouraging since I had already replaced the pump 3 yrs ago.

I think your prices are marginally high and I couldn't afford it anyway.

The replacement of the capacitor fixed the problem and I also sorted out a neighbour's pump with the same issue just last WE. I ordered a bunch of capacitor of Ebay from the UK.

Cheers

The Shower Doctors

Hi again
Glad you managed to get sorted.I noted you have already replaced a pump.Do bear in mind the St66 is a plastic pump designed to pump one shower.If this is installed in an appartment and is required to pump all the water, you would be better off with a brass pump for a longer life cycle.

Cheers
Steve:)

splendid101

Hi,

I'm having a problem with my pump too. It's a Stuart Mason 330n.

At the beginning of April it died and the water pressure was halved. I tried a variety of things but finally got it working by switching off the fuse for it at the main fuse box for the apt. and then replacing the fuse in the wall beside the pump. It worked for about three weeks and then one evening it was pumping non stop. It then stopped working and the water pressure became almost non existent. It came back on briefly as I was going to bed but by morning it was dead.

It was just emitting a buzzing sound which I've since learned means a blown capacitor.

I called the Shower Doctors and the engineer replaced the capacitor and also replaced several parts which were broken from the water going through it too hot. The rubber washers had become very brittle - that seemed to be the main problem. This caused the water to be leaking though it making it pump more than necessary. Something along those lines according to the engineer.

Anyway, about a week after that it started pumping non stop again. It's been doing that the last few days. I've tried taking out the fuse in the wall for different lengths of time, I've done the same with the fuse in the fuse box. It may work for a little while but before long it starts up pumping without a break again.

I don't think I've any leaks anywhere although discovered a loose part floating around in the toilet cistern. Don't know where it belongs or how long it has been loose there but the cistern doesn't seem to be filling up all the time or anything like that.

I've probably gone on a bit long here so I'll just cut to the chase and ask if anyone has any advise?

Thanks in advance,

Alan

p.s. I also intend ringing the Shower Doctors 1st thing Monday morning. It obviously wasn't fixed properly, or may there have been some other issue which has arisen? The engineer on the day said the printed circuit board was fine.

yoshytoshy

I've had problems with two of these pumps ,one at home here and one at my parents house.

My pump would keep running ,so I unclipped the two cables that run to the float switches and tapped both outlets with a screwdriver (hard) while the pump was turned off. Haven't had any trouble since ,about three weeks ago.

The other pump was stuck and had blown the fuse ,replaced the fuse and left both taps open in the bathroom and gave the sides of the pump a good wallop until the water started to flow through it. Haven't had any trouble since.

Stuart turner recommend dismantling the pump to free it when it gets stuck and also recommend disconnecting the pipes to free the float switches. But what I did worked for both and took about five minutes.

splendid101

Hi Yoshytoshy,

Thanks for the speedy reply.

I don't know what float switches are and not sure I'd know what you meant by the outlets even if I knew what the float switches were. Can you explain what you mean in a bit more detail? Not sure how I'd unclip things either.

There are two cables leading off it into the immersion.

Also, what's the reasoning behind it? Seems a bit like battering the side of the TV to get a better reception.

In the middle of using the washing machine so don't want to knock it off at the moment.

Thanks a lot,

Alan