A
Andrew453
Hello
I'd be grateful for some help with an issue with my heating/hot water system please.
The mid-position valve, while it will move under the power of the actuator does not move the full extent of its range. Therefore, when on hot water only, it doesn't quite make it to the end of its travel such the the heating gets some hot water too and the radiators become hot. The central heating and hot water both work fine as far as I can tell - it's running them independently that's the problem.
There's some history to it:
1) The heating was last powerflushed in 2009 and treated with inhibitor.
2) I've had trouble with the actuator before, and replaced that. I've never replaced the valve itself, so it's at least 10 years old.
3) Recently, I had trouble with the mid position valve again. I thought it was the actuator, but when I dissassembled it I found that the valve itself had actually seized. I managed to free it up without removing it using some pliers, and it would travel the full extent of its range. The heating/hot water system worked fine for a bit.
4) A few weeks' later I noticed the present problem.
5) My hunch is that it's sludged/scaled up inside. If I move the valve down (i.e. towards mid position) with the manual lever on the side of the MPV and then pull it up again (i.e. towards hot water only), I can get the valve to move further to the end of its travel, but then there's a minor clunk from the boiler and it springs back a bit. (Naot sure if there's any significance to that behaviour).
6) I went up into the loft to check the H/E tank. It's very sludgy. The water itself is clear (or at least it was until I disturbed it), but there's about 5mm of sludge at the bottom. It has roughly the consistency and colour of a muddy puddle. I'm in a hard water area.
For various reasons, I really don't want to have to replace the valve if I don't have to. (Access is really really poor).
Here's my plan:
a) Fish all the sludge out the H/E tank.
b) Drain the system (without tying up the ball cock) until the exit water runs clear.
c) Tie up the ball cock, and drain until dry.
d) Exercise the valve to try to free it up.
e) Refill, adding Sentinel X200 and X100 (descaler and inhibitor).
f) Bleed etc.
g) Hope for the best.
My question is whether the X200 is likely to be effective enough to desludge/descale the valve and whether the above approach is the right one, at least initially. I'm not quite sure how the X200 works, given that you don't drain the system afterwards. Presumably, it just breaks the material down and it floats around forever more.
I imagine I'll end up having to pay someone to replace the valve if the above doesn't work, but given it's £30 for the chemicals versus £300 to replace the valve, I think it's worth a punt in the first instance.
Any advice welcome. Thank you.
I'd be grateful for some help with an issue with my heating/hot water system please.
The mid-position valve, while it will move under the power of the actuator does not move the full extent of its range. Therefore, when on hot water only, it doesn't quite make it to the end of its travel such the the heating gets some hot water too and the radiators become hot. The central heating and hot water both work fine as far as I can tell - it's running them independently that's the problem.
There's some history to it:
1) The heating was last powerflushed in 2009 and treated with inhibitor.
2) I've had trouble with the actuator before, and replaced that. I've never replaced the valve itself, so it's at least 10 years old.
3) Recently, I had trouble with the mid position valve again. I thought it was the actuator, but when I dissassembled it I found that the valve itself had actually seized. I managed to free it up without removing it using some pliers, and it would travel the full extent of its range. The heating/hot water system worked fine for a bit.
4) A few weeks' later I noticed the present problem.
5) My hunch is that it's sludged/scaled up inside. If I move the valve down (i.e. towards mid position) with the manual lever on the side of the MPV and then pull it up again (i.e. towards hot water only), I can get the valve to move further to the end of its travel, but then there's a minor clunk from the boiler and it springs back a bit. (Naot sure if there's any significance to that behaviour).
6) I went up into the loft to check the H/E tank. It's very sludgy. The water itself is clear (or at least it was until I disturbed it), but there's about 5mm of sludge at the bottom. It has roughly the consistency and colour of a muddy puddle. I'm in a hard water area.
For various reasons, I really don't want to have to replace the valve if I don't have to. (Access is really really poor).
Here's my plan:
a) Fish all the sludge out the H/E tank.
b) Drain the system (without tying up the ball cock) until the exit water runs clear.
c) Tie up the ball cock, and drain until dry.
d) Exercise the valve to try to free it up.
e) Refill, adding Sentinel X200 and X100 (descaler and inhibitor).
f) Bleed etc.
g) Hope for the best.
My question is whether the X200 is likely to be effective enough to desludge/descale the valve and whether the above approach is the right one, at least initially. I'm not quite sure how the X200 works, given that you don't drain the system afterwards. Presumably, it just breaks the material down and it floats around forever more.
I imagine I'll end up having to pay someone to replace the valve if the above doesn't work, but given it's £30 for the chemicals versus £300 to replace the valve, I think it's worth a punt in the first instance.
Any advice welcome. Thank you.
