x400 indirectley causing system to run cooler?

[cypher007]

I put some x400 into my old system to try and cure a kettling issue. after a few days it seems better but the system doesn't seem to heat up as well. ideas.

 

[Millsy 82]

The heat exchanger is probably cleaner so therefore the flow of water through the boiler will be greater so it will give the water less time to heat up.

Check what pump speed is on/ size of pump

 

[newcastle phill]

I don't think it works like that lol

 

[cypher007]

another thought, maybe its pushed some muck into the boiler, thus quietening it.

 

[AWheating]

probably just over thinking/ checking. turn your stats up if your cold

 

[cypher007]

watching temps on a digital k-type meter and the flow and return differential has dropped from 11-12 to 6-8, and the flow temp is struggling to reach into the 50's.

obviously the x400 has shifted something, but not sure I that's a good thing or not.

 

[cypher007]

ok temps before x400 with pump on setting 2 and boiler stat on 6 (max):

5min 34 diff 9
10min 38 diff 9-10
15min 43 diff 10
20min 46 diff 10
25min 50 diff 11
30min 53 diff 12
35min 57 diff 13
40min 62 diff 14
45min 67 diff 16
50min 71 diff 17-18

maybe trv's were closing, but I still have a rad in the hall that's dosent have a trv and both lockshields are fully open.

after x400 for about 5 days:

0min 23 diff 6-7
5min 28 diff 8
10min 31 diff 8
15min 35 diff 8
20min 38 diff 8
25min 41 diff 8
30min 44 diff 9
35min 47 diff 9
40min 50 diff 9-10

52min 58 diff 11

then about 30mins later with boiler cycling on its stat:

65 diff 10

so it appears to have made the differential more stable, but at the cost of a very long heat up.

 

[Millsy 82]

How big is the system?

 

[Ermintrude]

New boiler new boiler. It's been through the wars and as its in a low spot probably full of sludge. Blast it out with mains pressure and a wet vac. Use the capped grav circs

 

[galaxy_plumbing]

put your pump to 3

 

[cypher007]

the system is, I think, too large for this boiler.

28mm runs 10m to unvented and pump from there to rads.

some rads are more or less off due to truning down the trv's, but this is the list:

3 doubles
9 singles

probably only 8 of those are actually set to give off heat, and 3 of those are set to very low output.

 

[cypher007]

also bought a magnaclean 2, which I plan to fit this weekend, hopefully this will help trap any crud the x400 has put into circulation.

 

[Ermintrude]

What size is boiler

 

[cypher007]

apparently 11.7-14.7, guess it depends on what the gas pressure is set to.

 

[Ermintrude]

Probably fine without megaflow. But megaflow will eat all that heat during heat up

 

[cypher007]

the slow heat up is just running the rad circuit.

p.s. ive got a rm stelflow. im a bit of a skin flint and couldn't stomach the megaflow's price tag.

 

[cypher007]

if I get a intergas 18kw would that be better than going for a larger 24kw? as the smaller boiler can modulate down slightly lower.

 

[dominoman]

I had the same thing on mine. Used Sentinel X400 and two days later the system was pumping over badly. I can only think that what happened is so much muck gets loosened that it has clogged up a valve or a pipe on the return to the pump.

Definitely worth fitting a Magnaclean. But if it is bad you'll probably need a powerflush too.

 

[Ermintrude]

Get a proper boiler .

 

[Aquazone]

I have read quite a few posts, and the phrase p*****g into the wind comes to mind.

Advise from Ermintrude above is best bet.

 

[cypher007]

if I replace the boiler would it be a good idea to move it to where the unvented is? im thinking I don't really want the boiler heating water then circulating it round a 20m (flow return) length of 28mm pipe, as im guessing the losses will be quite high.

 

[Ermintrude]

Not if its lagged or in warm house.

 

[newcastle phill]

Cant remember but losses may be 10w per meter on 28mm, so not a huge amount

 

[chris watkins]

Cant remember but losses may be 10w per meter on 28mm, so not a huge amount

Bit more than 10 phill, according to my book 41 @ Delter T 39deg C so around 820 Watts for the 20 Metres, if its uninsulated it could be a lot more.

 

[newcastle phill]

Mines different

 

[newcastle phill]

That is insulated i think
So providing they are installed correctly with the building rrgs he can presume 10w per M according to that


Thats lifted from the
Domestic building services compliance guide 2013 ed

 

[chris watkins]

OK,can't argue with a man quoting from scripture but whats the chances it will have been insulated & with 17mm foam. :Angel_anim:

 

[newcastle phill]

No idea, but dont we all do things right lol....i mean....isnt that the only way lol
I presume he would be doing a proper job after all as then who knows what the losses could be. Besides i think hes yet to do it....so it may be done right[emoji12]

 

[cypher007]

wowsers mg_smile: . mine is totally unlagged. no wonder the system takes ages to heat up.

think I might get the plumber to fit it in he airing cupboard, if and when we change it.