heatrae sadia 25l 9004010.

[Matt0029]

Has anyone one fit or serviced one of these before; Heatrae Sadia 25l 9004010.
It a 25 litre hot water storage cylinder.

 

[Matt0029]

When I turn the hot tap on the solenoid is in the closed position. As this operates then the low water level sensor opens it again. So if opening the hot tap and the solenoid is closed. It would be gravity?

 

[Matt0029]

First time I've come across one like this before there expensive units

 

[John.g]

If it gravity then there has to be a air vent in the cylinder to allow the level to drop to fall enough to open the solenoid valve? maybe it contains a air bubble like the megaflo and the like?
Are there HW draw offs above the cylinder or on the same level?

 

[Matt0029]

It has a breather pipe coming out of the top. With no valve on it.

 

[John.g]

Is it a vacuum breaker?, if so, then any HW draw off has to lower than (at least) the level of of the low probe.

 

[Matt0029]

Thanks yes the draw off are all lower the the unit. Breather pipe has tundish on it.

 

[John.g]

Maybe worth checking that for scale build up, if its restricted then the flow from any hot tap will be restricted as well except its just a pure vent pipe,, any photo or description of the unit?.

 

[Ben-gee]

Check the breather pipe for blockage, kink, hernia.
If air can’t get into the unit - water can’t get out.

 

[Matt0029]

Check the breather pipe for blockage, kink, hernia.
If air can’t get into the unit - water can’t get out.

Thanks I think there is a filter in the breather pipe. But there isn't much distance between the bottom of the unit and the hot taps. Only 1meter tops. So 0.1bar.

 

[John.g]

I have a upstairs "1/2" cartridge tap gravity fed from ~ 0.25M that flows 4.0LPM, so if the water level in your cylinder is, say 0.15M above the tap then you might expect ~ 3.0/3.1LPM.

 

[Matt0029]

The distance between the base of the cylinder and the hot tap outlet is around 1meter. So this would give 0.1 bar pressure. What flow rate would this likely give?

 

[John.g]

Maybe 2.0 to 2.5 LPM based on my tap.qqqqqqqqqq 50 chacters to post

 

[Matt0029]

Thanks I don't think it is that at the moment. Possibly abit of an airlock/ breather pipe blockage.

 

[Matt0029]

If it does flow at a decent enough level. If were to fit dual flow taps. Doesn't mix in tap mixes after leaves the spout. Would single checks not be needed to avoid back flow

 

[John.g]

Probably not, I have a d/stairs mixer like that where it mixes in the spout, 3.0bar cold & 0.5bar Hot gravity, no problems.