Sundial Y v Sundial S

[matt1e]

I think I'll go down the Sundial Y route cos the room with the roomstat in don't have TRV's n I can forget the valve

Its the same with s-plan you won't need one either,in this situation(two locksheilds)
unless you have more than one heating zone

matt

 

[DIYedboy]

Eeerrr, I thought a bypass valve was needed with an S plan cos if both valves shut as a result of a fault, it'll stop the boiler blowing up if it keeps tryin to work . If I don't have to fit one of these things GREAT , have I got the wrong end of the stick?

 

[doitall]

You need a by-pass in most cases with an S plan.

 

[DIYedboy]

DIA...............do I need one?

 

[Goldberg]

When TRVs close the pressure in the system rises.

I think you meant MZVs

 

[DIYedboy]

I've just looked on the Honeywell bypass valve PDF...........Fudge me! a mere mortal like me isn't meant to understand that surely!

If my system doesn't have any TRV's can I forget the ABV?

 

[bengasman]

When TRVs close the pressure in the system rises.

I think you meant MZVs

coldberk displaying his lack of understanding again.

Untitled

• bengasman
• 31 Oct 2009
• 4

 

[kevplumb]

When TRVs close the pressure in the system rises.

I think you meant MZVs

is that your opinion based on your vast experience in the plumbing and heating industry
i think you talk pants

I've just looked on the Honeywell bypass valve PDF...........Fudge me! a mere mortal like me isn't meant to understand that surely!

will you be told its a freaking adjustable spring loaded tap

 

[DIYedboy]

Yes you lovely Kev!. of course I will be told..................but you need to tell me EXACTLY how to set the thing, a tap with a spring ain't that helpful

 

[bengasman]

I ususally do it as follows:

Close the bypass fully.
Turn the boiler on at minimum rate with the normal flow blocked.
Open the bypass little by little, whilst I hold the pipe just after the valve.
When I feel the pipe getting warm, I open it one more turn.

 

[kevplumb]

you fit it first

then tweak it till you get no noise from the boiler when the cylinder / trvs close down

hell fella we have talked you through far more complicated things than this

 

[DIYedboy]

Bengas.................thanks for that............but how do I 'stop the normal flow'?

 

[bengasman]

Bengas.................thanks for that............but how do I 'stop the normal flow'?

Shut the "balance" valve on the cylinder circuit, or close all the rads.

 

[DIYedboy]

Ahh, good one...............select HW only, then close the balance valve, n fire up the boiler on minimum, yeah, I can do that

 

[Goldberg]

If my system doesn't have any TRV's can I forget the ABV?

TRVs have nothing to do with the need for a bypass.