No Hot Water Again on SwiftFlow 100 Boiler

[bozzy]

I currently have only occasional Hot water from my Swiftflow 100 boiler i.e every now and then it will work. I have bypassed the DHW Flow switch with the water flowing and the boiler fires up no problem.

I therefore assume the problem is with the DHW Flow switch although the water pressure seems low and I only replaced the flow switch around 14 months ago. If I run the water and tap the switch this makes no difference.

I guess my question is; if the ball in the flow switch jams does this reduce the flow of water to the taps and if that is not the case is there anything else in or around the boiler that would cause low pressure as mains pressure seems fine. There is a spherical object which comes off the feed pipe just before the Flow switch but I don't know it's purpose.

Any advise would be much appreciated

 

[Beerlover]

The minimum flow rate for this boiler is 3.6 l/min. The boiler has a water throttle (lefthand pipe) which may have crud in it, It may be a scaled heat exchanger

Try cleaning the throttle first

 

[kevplumb]

View media item 26397
might help

 

[bozzy]

Thanks for the info I will clean out the throttle and let you know how I get on

 

[Beerlover]

If you put an email in your profile I (or kevplumb) can send you the MI.

 

[bozzy]

Profile updated, Thanks Again

 

[kevplumb]

Profile updated, Thanks Again

no it ain't

correction is now

ex my e mail is playing up and won't send

 

[bozzy]

Sorry.....

I didn't realise that you have to save each page individually

Al done now...I hope

 

[bozzy]

OK, I upped the pressure slightly, and to my delight the boiler fired up when I turned on the hot water tap........Unfortunately my joy was short lived because when I turned the tap off the boiler did not shut down, not good, turned water back on and off again but no joy stuck solid.

Shut down the boiler, removed the reed switch from the flow switch and the boiler did not fire up so It must the mechanical part of the flow switch. What a pain...

Does anyone know where I can get a replacement at a good price?

Thanks again

 

[nickso]

be aware then that you need to remove the combustion case, inner cover, pilot assembly and burner to remove the flow switch.

i would be wary of you doing all of that with no prior experience.

 

[Beerlover]

No you don't

It is beneath the combustion chamber, and why would he touch the pilot and burner? Are you looking at the same boiler

 

[bozzy]

I have already replaced the flow switch once and all you have to remove is the front chamber cover then undo the pipe union and lock nut It's a bit fiddly but no need to remove the burner or anything else.

 

[nickso]

No you don't

It is beneath the combustion chamber, and why would he touch the pilot and burner? Are you looking at the same boiler

the locknut is in the combustion chamber.

 

[nickso]

I have already replaced the flow switch once and all you have to remove is the front chamber cover then undo the pipe union and lock nut It's a bit fiddly but no need to remove the burner or anything else.

ok so you have experience, good.

you are lucky the backnut isn't on very tight. if it is it's burner out.