choosing a replacement pump and other set up advice and help needed

[chris1970]

hi,


i had a new boiler fitted in summer and just starting to use it :

old boiler olympic 38/50 CF with no trv's and wilosmart 25/6 pump set to no . 2

new boiler is worcester 15ri with trv's on all rads except hall where new wireless stat is .

fitter got it working but had to set pump to no. 3 because the boiler was tripping off i presume on overtemp.

the old pump had noisy bearings and he said to replace it.

system was drained all summer and i got a new pump last month ( grundfos aplha 2L )

i'm just using new system for first time and having trouble with it.

overpumping depending on pump settings and boiler temp.
noisy pipes and air in system.
boiler struggling and switching off.
hall not getting upto temp. in cold weather.

i have exposed the 15mm feed and 22mm vent pipe just above the boiler and they attract a magnet so i'm thinking to cut them out and make some improvements ?

boiler got moved 6 inches so the vent doesn't go straight up from boiler now , is that a problem ?

i could use the existing vent pipe for a new feed and put in a new vent above the boiler.

the vent is currently only 400mm above the water level , is it good idea to increase the height ?

the 15mm feed gets hot right way to tank , the vent pipe is always cold but i have seen it pumping over when the pump was set to fixed high and boiler temp was up.

to get it working now i have had to remove some trv heads and set the pump to variable no . 2.


i was hoping to run the pump a bit faster to try and get house heating up quicker and not to heat bedrooms.


i also have some F2 silencer to try and reduce the clanging but should i modd the pipes and maybe remove the downstairs rads and clean them out ?

small 3 bed house was build in 1980 and has 5 double rads and 3 singles , just boiler in kithen and airing cupboard directly above and tanks in loft .

2 way valve for water Y-plan system .


thanks for looking,
chris

 

[Millsy 82]

I would get the installer back out to look at it.

 

[chris1970]

thanks for reply,
problem is i have changed the system and the guy lives 200 miles away ,
i got the boiler replaced on the cheap on one of those government energy saving schemes.
i will call the company if i can't set it up.
i have fiddled with it today i have moved the thermostat away from the front door where it was in a draft and already it is reading 3 deg higher.
i have removed some trv heads so able to set the boiler bit hotter and with pump in auto mode seems better .
not ideal but at least the boiler isn't switching off now and over pumping.
i tried calling honeywell today to see if my room stat is faulty sometimes it doesn't call for heat when the temp. drops , when i do the wireless signal strength it does say 5 for max. signal but it alternates from 5 to 0 every few seconds , i'm not sure if that's normal or if the unit is faulty.

i don't know wheather to cut out the feed and vent pipes and see if they are blocked , the magnet does attract abit but could it just have small amount or iron on inside not affecting the flow.

the rads do get hot and only one downstairs one which is slightly cooler in the middle ,

i think the basic problem is the trv's and the flow and is that new pump too powerful.

the pump has 7 settings 3 fixed 2 variable flow and 2 variable temp. or something - i'm set to variable flow no. 2 which adjusts when trv's close.

i'd like to improve the pipework and run on fixed if the boiler keeps tripping off on overheat.

tempted to fit a simple room thermostat clean downstairs rads and fit just lockshields.

i have bulldog trv's , if i just remove the heads is that the same as opening lockshields fully ? what's the best to maximise flow downstairs ?

i'll try adding some pics.
chris

 

[dmheat]

I would agree with the above...

 

[chris1970]

surely its worth me cleaning the system and trying the F2 silencer before getting pro in ?
another thing i forgot to mention is that before the boiler was fitted and trv's etc i used to be able to drain the system in minutes now it takes hours and barely drips out.
it's difficult to know what's going on because so many changes and i'm always adjusting things.
if i put some system cleaner in either x400 or x800 or F3 etc is there a chance i may block up the pump ? should i remove rads first and get out what i can then flush it ?
i did clean the upstairs rads. in the summer , i had upstairs replastered so the rad brackets got taken off , another problem is pipes touching the floor boards and no movement, rubbing etc ,, making noise ,
i need to decide what to do and have a plan.

i'm not working so i can't just throw money at powerflushes etc

 

[SimonG]

I concur. Seems strange.

 

[dmheat]

Blocked cold feed all day long

 

[Millsy 82]

Blocked cold feed all day long

I disagree I reckon not piped correctly. But without looking it's impossible to say.

 

[SimonG]

Seems a bit too much diy.

 

[dmheat]

I disagree I reckon not piped correctly. But without looking it's impossible to say.

If a magnets sticking to it,it's 100% at least partially blocked,not much to disagree on there. Also fits with pumping over on high pump speed, and if the systems been drained to fit the new pump, now it's churning air and gurgling, it's not filled up properly and/or it's pulling in air

 

[PhoenixServices]

Is the cold feed and vent by the boiler and pump in the airing cupboard?

 

[Dotty]

Smacks of a diy job.

Best bet is to get a competent gsr in rather than trying to get yourself out of a hole.

Thread closed.

 

[chris1970]

Is the cold feed and vent by the boiler and pump in the airing cupboard?

the vent and feed are right next to each other just after the boiler , the connections are in the floor space under the airing cupboard and directly above the boiler.
i have cut kitchen ceiling to test with magnet,

the boiler got moved 6 inches to left so now the pipe work has several 90 bends in .

i think originally the pipes were laid out quite well .

probably keeping pipes the same but making sure they are clear will be fine for another 30 years , but i'm wondering if increasing feed to 22mm will help to prevent pumping over and future blockages.

i'm going to get a pro to do any soldering etc but i want to get advice and knowledge first so i can get it designed well and make sure it's as good as can be.

i'm unable to add photos for some reason