We only have a handwheel bypass valve. How do we establish whether this is open/closed to the correct degree and which way does one turn it o close/open? How does this fit in with balancing the radiators? Thanks in anticipation.
How to set a manual (handwheel) bypass valve?
- Thread starter patagonia
- Start date
Bengasman-
Well, the plumber who installed the boiler referred to it as a bypass valve. Is there no such thing as a manual bypass valve or are you implying that anything other than an auto b.v. is useless. The boiler certainly seems to be on a lot and as you will have noticed we certainly do have a lot of problems. When we can get someone to come and fit a new motorised valve and flush the system etc. we'll get an auto b.v. fitted as well. I just wondered if there was anything I cd do to improve the situation in the meantime. Chances of getting anyone in before Xmas are somewhat slim I fear.
Well, the plumber who installed the boiler referred to it as a bypass valve. Is there no such thing as a manual bypass valve or are you implying that anything other than an auto b.v. is useless. The boiler certainly seems to be on a lot and as you will have noticed we certainly do have a lot of problems. When we can get someone to come and fit a new motorised valve and flush the system etc. we'll get an auto b.v. fitted as well. I just wondered if there was anything I cd do to improve the situation in the meantime. Chances of getting anyone in before Xmas are somewhat slim I fear.
In a nutshell, yes the only real bypass is an auto-bypass. If you have a 3-port valve, close the bypass as you won’t need one.
If you have to live with a manual, do the following when you have 2 zonevalves. Turn boiler off and let cool off. Close manual bypass completely. Close all radiator valves. Turn heating ONLY on. Turn bypass open half a turn at a time until you hear flow or feel pipe coming out of getting hot. Leave in that position. Job done
If you have to live with a manual, do the following when you have 2 zonevalves. Turn boiler off and let cool off. Close manual bypass completely. Close all radiator valves. Turn heating ONLY on. Turn bypass open half a turn at a time until you hear flow or feel pipe coming out of getting hot. Leave in that position. Job done
Bengasman - we don't have a 3 port valve but we have three 2-port valves. Which way do you turn the gate valve? Is it clockwise to close and anti-clockwise to open?
by all means, this is a forum, not an ego trip
I forgot to mention that the towel rail is on (2 lockshield valves) whenever the boiler is firing because a zone is calling for heat. Will this interfere with your suggest method re bypass valve and would it throw out an auomatic bypass valve if we fit one? I notice that there is a big reduction in the difference between boiler flow and return when the upstairs zone switches off. Is this because the bypass gate valve isn't set right?
Yes, I realise this which is why I was asking what to do about the bypass gate valve. It tees off the cylinder flow or return (22mm) somewhere and goes from the cellar to the lst floor so presumably it must be costing us quite a bit as it is hot all the time, We are at home most days being elderly so the ground floor is on all day in this weather, with some of the rooms turned down to a mid setting. In any case, as we have solid walls one wouldn't want to leave it off too long as it takes ages to get the house warm again. The boiler outflow goes up to just over 70 and the difference is less than l11 degrees acc. to my battery operated device and I can hear it kettling like mad. Sounds as if it is boiling. The clip on thermometers on the pipes in the cellar certainly aren't accurate; acc. to them the flow is only 60 but it must be more than that on the 2nd highest boiler setting surely, and the return is 57 but I'm sure there is more difference than that, even if not enough.
If your towel rail is on all the time, shut the manual bypass valve, it's pointless!
A problem you might have (I can't remeber all your posts!) is that if the valves on the towel rail are wide open, they'll act like a short circhit and drop the pressure available to circulate the water round the rest of the system. That would look like a sludgy system (qv!). Only one of the valves needs to be turned down, but probably as low as only half a turn open. (See Balancing in the FAQ section)
Kettling - isn't your boiler fairly new?
Then it shouldn't kettle. What model is it - sorry if you've already said.
A problem you might have (I can't remeber all your posts!) is that if the valves on the towel rail are wide open, they'll act like a short circhit and drop the pressure available to circulate the water round the rest of the system. That would look like a sludgy system (qv!). Only one of the valves needs to be turned down, but probably as low as only half a turn open. (See Balancing in the FAQ section)
Kettling - isn't your boiler fairly new?
Then it shouldn't kettle. What model is it - sorry if you've already said.
Kingfisher MF conventional flue - 5 yrs. When we had our first new boiler 30 odd yrs ago (different plumber), we were told never to touch the valves on the towel rail so we haven't. That's something to look into. Cd explain why there is so little difference betw. flow and ret. to the boiler even though there is a difference at the rads. Thanks.
I turned off all the rads bar one and this time also turned off the flow knob on the fan convector in the dining room which I usually leave open without putting the fan on and now that we are running the boiler at the 2nd highest setting, the drawing room rad and its return pipe did seem to get hotter. I suppose having 2 fan convectors on the system, where the valves are supposed to be fully open, it complicates things and makies balancing difficult, esp. when things are not on all the time. There was a slight difference between top and bottom but if there is supposed to be a l2 degree drop between flow and return is this not to be expected. One problem is that if one turns the l/s down on rads nearest the boiler they start to hiss or whistle when tvs turn off. Whoever put the tvs on put them in the hall and landing where the zone therms. are but presumably this doesn't matter if one leaves them on max?
Thanks to everyone for help.
Thanks to everyone for help.
Chris - Thinking about all this, what I don't understand is why plumbers who have been here whom I have told about the towel rail situation have recommended fitting an auto-bypass. I have now closed the manual valve and the differential between flow & return seems to have improved, though it reduced again when I opened the dining room fan convector. Perhaps I should leave the fan on low to dissipate some of the heat even though we are not using the room.
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