Problems Venting System
- Thread starter Tommohawk2
- Start date
- Joined
- 5 Dec 2025
- Messages
- 38
- Reaction score
- 5
- Country
Sorry to be slow.. lots other stuff to deal with, but..
RESULT! Took a while to bleed air from system but now running nicely both CH and HW. Initially pump only using 7w on CC3 as before but after some gurgling etc it's now 40w on CC2. I guess I'll switch to PP2 once it's settled.
I'll need to fully flush X400 after a couple of weeks. I'm thinking ideally I'd fit Magna clean or similar but the boiler return isn't very accessible.
Huge thanks for your help with this.. your suggestion that pump had restricted feed even though feed tank right next to it, gave me the confidence to strip the pipework leading to it. Maybe this thread will help someone else in the future.
BTW pump reading 40w on CC2. Do you want any other readings?
RESULT! Took a while to bleed air from system but now running nicely both CH and HW. Initially pump only using 7w on CC3 as before but after some gurgling etc it's now 40w on CC2. I guess I'll switch to PP2 once it's settled.
I'll need to fully flush X400 after a couple of weeks. I'm thinking ideally I'd fit Magna clean or similar but the boiler return isn't very accessible.
Huge thanks for your help with this.. your suggestion that pump had restricted feed even though feed tank right next to it, gave me the confidence to strip the pipework leading to it. Maybe this thread will help someone else in the future.
BTW pump reading 40w on CC2. Do you want any other readings?
Circulating pretty well now
CC2 (40W) is circulating 16.67LPM at a 4.9M pump head.
Based on the above, I would expect
PP2, 11.3LPM at a 2.25M pump head
PP3, 15.02LPM at a 3.98M pump head
Suggest initially change to PP3, post power.
Where was the severe pipe blockage, was it upstream (before) of the Vent??
CC2 (40W) is circulating 16.67LPM at a 4.9M pump head.
Based on the above, I would expect
PP2, 11.3LPM at a 2.25M pump head
PP3, 15.02LPM at a 3.98M pump head
Suggest initially change to PP3, post power.
Where was the severe pipe blockage, was it upstream (before) of the Vent??
Last edited:
- Joined
- 5 Dec 2025
- Messages
- 38
- Reaction score
- 5
- Country
It was in the straight section of speedfit with the 2 Tees to vent and feed. TBH I was so pleased to find any blockage I didn't check precisely, but I'm pretty sure it was at the feed T, so after the vent.
PP2 15w, PP3 28w with HW and CH on
PP2 15w, PP3 28w with HW and CH on
DIYnot Local
Staff member
If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Are you a trade or supplier? You can create your listing free at DIYnot Local
