Flowmax 180 combination

[darren6645]

In most other circumstances with a noisy 4 series you'd certainly be right, however heating a thermal store is like heating a massive LLH, so the water flow rate through the heat exchanger "should" be completely unimpeded, which is where a lot of noise issues on these boilers come from (typically 30/38kw versions fitted to restrictive circuits with small pumps) But an 18kw on a Store should not suffer from noise due to the output, it will likely be a slowing pump/debris collecting in the heat exchanger or probably mixture of both.

I'm guessing the pump your relating to is the pump in the boiler abs not the 2 at the tank.

 

[ianmcd]

I'm guessing the pump your relating to is the pump in the boiler abs not the 2 at the tank.

There isnt a pump inside your boiler, just the two up at the Cylinder

 

[darren6645]

Ah ok. When I looked at a parts list and exploded diagram thought it showed a pump?
My mistake.

 

[ScottishGasMan]

Ah ok. When I looked at a parts list and exploded diagram thought it showed a pump?
My mistake.

Some of the parts lists show a pump for these but its an optional external kit, there is never a pump inside them. One pump will pump the heat to your radiators, one will pump from boiler to store (easy to tell, turn heating off, the pump still running is the one for boiler)

 

[darren6645]

Some of the parts lists show a pump for these but its an optional external kit, there is never a pump inside them. One pump will pump the heat to your radiators, one will pump from boiler to store (easy to tell, turn heating off, the pump still running is the one for boiler)

I've always thought that but someone said they're was a pump, thanks for confirming they're isn't.

 

[darren6645]

Quick update. Drained system and all rads today, new filter fitted, refilled system plus 3 litres x400, rads bled, all back on. Will keep it in for 2 weeks, drain, refill and drain another 4 times, then refill plus 3 inhibitors, hopefully does the job otherwise I'm fooked!
Thanks for all your help ianmcd and ScottishGasMan, I'll let you know how I get on in a few weeks.

 

[darren6645]

Tried to upload a video of the boiler noise but keeps saying there is a problem? 45 sec clip mp4?

 

[darren6645]

In most other circumstances with a noisy 4 series you'd certainly be right, however heating a thermal store is like heating a massive LLH, so the water flow rate through the heat exchanger "should" be completely unimpeded, which is where a lot of noise issues on these boilers come from (typically 30/38kw versions fitted to restrictive circuits with small pumps) But an 18kw on a Store should not suffer from noise due to the output, it will likely be a slowing pump/debris collecting in the heat exchanger or probably mixture of both.

Sorry to bother you but could I send you a video (somehow) with my boiler noise?
Cleaner is in, cleaned filter yesterday small amount of sludge. Noise is obviously still there wasn't expecting it to go over night but when I drain it next I'm wondering if its worth chaging circ pump, if that's possible problem before I spend money on inhibitor and wasting it draining after.
Noise is once again only when demand is high and what I'm guessing is full flame. If I reduce temp set point and bring it up along with the tank temp, no noise it's only when there's a large difference and boiler is trying to achieve tank temperature as per set point on boiler.
If the pump was the problem why would this only make the noise when on full flame as once boiler throttles back noise is gone and everything ticks over quietly.
When the noise is heard if I slow the pump down it get worse?

 

[ianmcd]

when you have the system drained remove the pump head , it is simply 4 x Allen bolts and will pull off, check for debris in the impeller and pump body

 

[darren6645]

when you have the system drained remove the pump head , it is simply 4 x Allen bolts and will pull off, check for debris in the impeller and pump body

Great idea, I've attached an image of my pump so just pull off front and check, after electrically isolating and draining of course.

 

[ianmcd]

Great idea, I've attached an image of my pump so just pull off front and check, after electrically isolating and draining of course.

yes exactly that ,your pump also has isolating valves either end for removing without draining but I think you have ballofix ones and not gate valves, if you do have ballofix ones dont touch them or likely they will leak, your pump is stamped BG but is actually grundfoss

 

[darren6645]

yes exactly that ,your pump also has isolating valves either end for removing without draining but I think you have ballofix ones and not gate valves, if you do have ballofix ones dont touch them or likely they will leak, your pump is stamped BG but is actually grundfoss

Cheers again, I'll give that a look at. If it was pump related any idea why it goes quiet once upto temp?
I have a couple of videos but can't seem to upload them, I've compressed them but still having problems.

 

[ianmcd]

Cheers again, I'll give that a look at. If it was pump related any idea why it goes quiet once upto temp?
I have a couple of videos but can't seem to upload them, I've compressed them but still having problems.

As the system heats up the boiler modulates down, so producing a lot less heat so the boiler will be quieter

 

[darren6645]

As the system heats up the boiler modulates down, so producing a lot less heat so the boiler will be quieter

Ok yeah when I think about it if the boiler is noisey this will be emphasised by the pump? So sounds more boiler related than pump but I'll check them all the same.

 

[ianmcd]

Ok yeah when I think about it if the boiler is noisey this will be emphasised by the pump? So sounds more boiler related than pump but I'll check them all the same.

the pump circulates the heat out of the boiler so if the pump is not set correctly and running correctly the heat cant get out of the boiler fast enough so the boiler gets noisy