Problems Venting System

[Tommohawk2]

Your system filled up after draining so it wasn't blocked. So it couldn't go to mains pressure

Yes I agree completely. I'm just pointing out to others there is a potential risk if their system was blocked.

 

[Johntheo5]

Did the heating man come today??

 

[Tommohawk2]

Yup. He was actually really good. Tomorrow I'm going to drain again, he's then going to arrive and replace sludged section of pipes, and check pump. Then I'll refill adding x400. Hopefully should then be good and I'll do final flush and refill after few weeks. I'll report back once up and running tomorrow.

 

[Tommohawk2]

Not good. Removed suspect section of copper pipe but wasn't really badly blocked. Pump was pretty rammed with debris so replaced that and 3 port valve. But.. still really minimal flow. Really puzzling.. and now backfill seems really slow as though feed blocked. Feed blockage in itself wouldn't restrict circulation of course but it tees onto main flow just after vent and if the t were completely blocked that could restrict both feed and main flow to pump.
Curiously the section of pipe before the pump including the pipe to vent and inlet has been replaced with speedfit. Seems odd and I'm just wondering if this has blocked before. Wish we'd removed that speedfit section to check now. Heating guy seems switched on but even he seems puzzled.

 

[Johntheo5]

Did you replace it with another ups3?, if not post the make/model.

 

[Tommohawk2]

Did you replace it with another ups3?, if not post the make/model.

UPS4 GO 25-65 130.

 

[Johntheo5]

Not familiar with that model but at least I think it displays the power in watts and eventually if you get/have the Go App you can read off the flowrate remotely. For the moment, what mode/setting is it on and what is the power output, if displayed, you might then change to HW heating only and post the data again.
I will have a read up of the I manual.

 

[Tommohawk2]

OK thats interesting. TBH I'm done for the day - bizarrely I've also been trying to sort my daughter's heating issues and looks like she needs a new boiler. A frustrating and damn expensive day. I'll take a look tomorrow - is it bluetooth type hookup?

 

[Johntheo5]

Presume it is but not required as the pump's display gives enough data to derive the flowrate from the pump curves which I see in the manual.

On what basis are you getting minimal flow?? and was this on rads only or HW heating only or both on?.

Did you glance at the pump display or do do know what mode/setting it's on, anyhow once you're back there tomorrow will be able to figure out at least what is circulating etc.

 

[Tommohawk2]

When I say no flow, I mean rads and hot water not getting hot. There is very slow flow, and bathroom rad got hot after over an hour but no others. Cylinder loop slowly gets hit at bottom but still cool at top.
I think it's been set just on CC3. At one point it was displaying numerics.. . I think between 4-9 from memory, but not sure if at that point was rads, HW or both. I'll check tomorrow.
Sounds like low numbers means high resistance?

 

[Johntheo5]

Personally, I wouldn't, under almost any circumstances run on CC3 as the pump head will be over 6M at most flowrates and (the UPS3) can and has caused havoc on some OV systems, the UPS4 pump curves are almost identical to the UPS3.

The 4-9 numbers are almost certainly the power in watts (W) and on any one of the CC curves shouldn't be this low, even with a perfectly clean system, if the pump is deadheaded, ie, the pump outlet valve closed, CC1 should read 16W, CC2....20W and CC3...23W. So problen is IMO not high resistance and either (still?) air locking or something else.

Its surprising that the cylinder coil is hottest at the bottom as the normal coil circulation is from top to bottom but that in itself should not be a problem. No harm to check that the pump is orientated correctly tomorrow.

 

[Tommohawk2]

Thanks for that. TBH it's exactly as it was yesterday before replacing parts. Pump orientation has been checked. Coil is Def plumbed bottom to top.
So, wattage may suggest still airlock? But when I connected to mains to backfill there was minimal flow into FE tank. Maybe FE is blocked which is causing big airlock?

 

[Johntheo5]

Suggest first thing tomorrow is to spend just a few minutes in changing the pump from (If) CC3 to CC1 and observe the power, a few minutes will do. then, depending on that test, boiler off, open the drain off valve just sufficiently to see what kind of ball cock make up is required to keep the bottom of the F&E cistern covered with water, that should tell you what kind of blockage you have, if any, in the cold feed.