|
|
Post by tomplum on Dec 16, 2017 15:34:37 GMT
|
|
|
|
Post by rocketmanbkk on Dec 16, 2017 15:44:48 GMT
That’s turning it into a sealed system. Can be done. What’s the pros & cons of it? Open vent v sealed system? Basically Rocky no more F & E tank and any of that black sludge in the pipework but I've never seen one where the vent isn't as a swan neck above the F & E tank. Yeah, but is there an advantage sealed v open vent? |
|
|
|
Post by battle1066 on Dec 16, 2017 15:50:39 GMT
Basically Rocky no more F & E tank and any of that black sludge in the pipework but I've never seen one where the vent isn't as a swan neck above the F & E tank. Yeah, but is there an advantage sealed v open vent? Sealed is best because you can have mains pressure hot water at the taps without a pump in the system. |
|
|
|
Post by tomplum on Dec 16, 2017 16:16:40 GMT
Its a matter of opinion, as battle says having equal pressure is a good point, a bad point is, if the water goes off, you have no water at all, So there are many good and bad points,
I think My vote would be, unvented because its easier to work on,less likely to airlock,
perhaps a vote is in order ?
|
|
|
|
Post by endfeed on Dec 16, 2017 16:17:05 GMT
 cheers tom....
|
|
|
|
Post by tomplum on Dec 16, 2017 16:21:02 GMT
you're welcome mate,  |
|
|
|
Post by endfeed on Dec 16, 2017 16:23:09 GMT
I sooner unvented,less chance of airlock s when filling back up👍
|
|
|
|
Post by battle1066 on Dec 16, 2017 16:33:06 GMT
Its a matter of opinion, as battle says having equal pressure is a good point, a bad point is, if the water goes off, you have no water at all, So there are many good and bad points, I think My vote would be, unvented because its easier to work on,less likely to airlock, perhaps a vote is in order ? I would say open vented is nearly always fixed on first visit - sealed can take a return visit - combi is nearly always a return visit, unless you've got a van full of spare bits. The above is only my opinion but a vote is a good way to find out. |
|
|
|
Post by rocketmanbkk on Dec 16, 2017 16:35:05 GMT
Its a matter of opinion, as battle says having equal pressure is a good point, a bad point is, if the water goes off, you have no water at all, So there are many good and bad points, I think My vote would be, unvented because its easier to work on,less likely to airlock, perhaps a vote is in order ? A chap I know a few years ago put a pressure vessel on the vent ( took the F&E out). What’s your opinion on doing this? I’m not talking unvented cylinders where the hot & cold are balanced. I’m taking a system boiler with hwsc. |
|
|
|
Post by battle1066 on Dec 16, 2017 16:47:00 GMT
Its a matter of opinion, as battle says having equal pressure is a good point, a bad point is, if the water goes off, you have no water at all, So there are many good and bad points, I think My vote would be, unvented because its easier to work on,less likely to airlock, perhaps a vote is in order ? A chap I know a few years ago put a pressure vessel on the vent ( took the F&E out). What’s your opinion on doing this? I’m not talking unvented cylinders where the hot & cold are balanced. I’m taking a system boiler with hwsc. PB often does the upgrade from open vent to sealed system and comments about leaks needing to be added as an extra because of the system changing to mains pressure on a standard system boiler and all associated pipework, taps, rad valves etc. |
|
|
|
Post by tomplum on Dec 16, 2017 17:23:56 GMT
chap I know a few years ago put a pressure vessel on the vent ( took the F&E out). What’s your opinion on doing this?
that would't work, he's need to fit a means to fill it ( filling loop) and a PRV for safety,
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Dec 16, 2017 17:54:04 GMT
The benefits of a sealed system is they are cheaper to install on new builds, they cut out a lot of oxidisation because they are not open to atmospheric pressure unlike the vented system. Pressurised water heats quicker and takes less energy to do so, no air locking like the vented on fill up. Small pressure loss on a sealed system is normally when the pump is set to high which causes cavitation and that air escapes through the AAV dropping the pressure and some people think they have a small leak. I still like a vented system though  |
|
|
|
Post by crowsfoot on Dec 16, 2017 19:14:42 GMT
Its a matter of opinion, as battle says having equal pressure is a good point, a bad point is, if the water goes off, you have no water at all, So there are many good and bad points, I think My vote would be, unvented because its easier to work on,less likely to airlock, perhaps a vote is in order ? A chap I know a few years ago put a pressure vessel on the vent ( took the F&E out). What’s your opinion on doing this? I’m not talking unvented cylinders where the hot & cold are balanced. I’m taking a system boiler with hwsc. It will certainly fix any "pump over" fault on a vented heating system and possibly more acceptable than having no expansion pipe (just using the 22mm cold feed method). You will need a filling loop to fill the system and PRV for safety Someone will have to keep a regular check on the pressure (water level) gauge. It's not an aproved method so no boiler manufacturer will say fit an expansion vessel and don't bother with the F&E tank! In fact it will say the opposite that it must be connected to an open vent. Just to re-cap - We are talking about an old fashioned vented system that's got some problem with the open vented feed and expansion tank so that we're now doing away with it altogether. It's all very interesting stuff though. |
|
|
|
Post by crowsfoot on Dec 16, 2017 19:36:39 GMT
The gaffer of the 2nd firm I worked for (the same workplace that I featured in Anglers Corner 1) used to do his own invention of taking the heating flow not from the boiler but from the primary gravity flow pipe near the cylinder.
It saved pipework and would give the primaries a little boost when the pump was on for the heating and he would also get away with a long run of horizontal pipework on his gravity primaries which may not have even worked without using that method.
I often wonder what the plumber who gets called out to it made of it all.
It was wrong, yet for some of the jobs we did it may have been right for that job (this was before anyone had ever thought about pumping the primary circulation pipes!
|
|
cheers tom....
