Indirect water cylinder

[desktop987456]

what does mSS mean

Don't know but see attached extracted from a manual for indirect. I have read a term mWC (meters water column). This is similar to mine but a bigger tank volume (500 litres). I am assuming mine with a lower flow rate than 6.5m3/hr would have less mWC (~1m?).

heat only boiler then that 6M Wilo will also be fin

Its a heat only boiler with no pump inside it. I have bought an external wilo pump (pico) with 6m head.

Not sure about pipe size to use and hence the question: should 22mm be fine considering the boiler has 22mm flow and return pipe to it. or go with 28mm pipe.

 

[Johntheo5]

Don't know but see attached extracted from a manual for indirect. I have read a term mWC (meters water column). This is similar to mine but a bigger tank volume (500 litres). I am assuming mine with a lower flow rate than 6.5m3/hr would have less mWC (~1m?).

That would only be true if the same coil is used in your cylinder, which I doubt, IF it was the same coil and assuming you will circulate 1.0m3/hr max then the coil resistance would fall to 2.9*(1/6.5)squared, 0.06mWc which is only 2.4inches, highy unlikely IMO, I still think you will be fine but no harm in asking the supplier to clarify this with Alarko, I tried emailing them just now but getting "address not found".

Don't know but see attached extracted from a manual for indirect. I have read a term mWC (meters water column). This is similar to mine but a bigger tank volume (500 litres). I am assuming mine with a lower flow rate than 6.5m3/hr would have less mWC (~1m?).

Its a heat only boiler with no pump inside it. I have bought an external wilo pump (pico) with 6m head.

Not sure about pipe size to use and hence the question: should 22mm be fine considering the boiler has 22mm flow and return pipe to it. or go with 28mm pipe.

I have one of those 6m Wilo Yonos Pico pumps, a lovely pump with infinite settings in Constant Pressure & Proportional Pressue modes.

I dont think you will have any problem with 22mm piping.

One other thing, you quote a cylinder capacity of 120L but one would think the model "160" is 160L capacity?, even better.
Will your (boiler) system be sealed??

 

[fixitflav]

Its a heat only boiler with no pump inside it. I have bought an external wilo pump (pico) with 6m head.

When you said "Yes, putting the pump on return pipe to boiler. In a system boiler that's where the pump usually is. So it is pumping into the HEX." I assumed you meant your new HW boiler is a system boiler. If it's heat-only you can decide whether the pump is on the flow or return.

Not sure about pipe size to use and hence the question: should 22mm be fine considering the boiler has 22mm flow and return pipe to it. or go with 28mm pipe.

Johntheo5 and I have already said 22mm will be fine, just like on the vast majority of normal-sized systems.

 

[desktop987456]

Alarko, I tried emailing them just now

Same here, that is why I came to this forum for advice.

one would think the model "160" is 160L capacity

Must have been a typo if I said 120litres anywhere. I can confirm it is 160 litres.

Will your (boiler) system be sealed?

Yes, even though it is an open vent boiler but I have checked with Viessmann, it can be put in a sealed configuration.
I'll be led by your guidance, in one of the posts you advised on putting the pump on inlet (or return to boiler) and External EV just before the pump, correct?
Thanks in advance.

 

[Johntheo5]

Yes, pumping into the boiler return.

 

[desktop987456]

Yes, pumping into the boiler return.

One last thing, where do I put the filling loop and pressure guage in sealed configuration? Do you have a drawing as I am buying things in pieces; have an external EV without a valve and pressure guage.

 

[Johntheo5]

Something like this should do the job, you require a pressure relief valve set to 3.0bar, a pressure gauge, and a filling loop with isol valves. You shouls be able to buy the kit without the EV.