Hot water secondary

[PhoenixServices]

Does anyone know of a pipe manufacturer or material like plastic that can be used on a hot water secondary. Needs to be cabled through joists hence the need for the flexibility.
Cheers guys

 

[ShaunCorbs]

mlcp or copper no plastic

 

[PhoenixServices]

Cheers Shaun didn't even think of mclp.
Second question which is the best manufacturer for mclp re: cost and quality.

 

[SimonG]

What size is the hot water flow?

 

[Chalked]

Cheers Shaun didn't even think of mclp.
Second question which is the best manufacturer for mclp re: cost and quality.

Uponor press fit, or q&e shrink fit. I use both, the shrink fit is cheaper and has better flow characteristics.

 

[ShaunCorbs]

Cheers Shaun didn't even think of mclp.
Second question which is the best manufacturer for mclp re: cost and quality.

Uponor Mlcp press

 

[PhoenixServices]

Hot water going out is 22mm then secondary coming back in 15mm.

 

[ShaunCorbs]

Hot water going out is 22mm then secondary coming back in 15mm.

Out of interest why do you think you need a secondary return or is it specd?

 

[SimonG]

Hot water going out is 22mm then secondary coming back in 15mm.

That's a shame, thought you could have got away with 10mm copper.

 

[PhoenixServices]

It's an old Georgian house, we are putting a unvented in the loft with boiler. The longest run to an outlet is at least 20m directly. Previously had a gravity hot water secondary in copper+ plastic+lead+ iron

 

[ShaunCorbs]

It's an old Georgian house, we are putting a unvented in the loft with boiler. The longest run to an outlet is at least 20m directly. Previously had a gravity hot water secondary in copper+ plastic+lead+ iron

One or two cylinders ? And how many bathrooms

 

[chris watkins]

I have read a few bits of info on this & each has stated that plastic is not suitable for "continuously operated" secondary returns as it has not been tested for this inline with the manufacturing BS's.

However I would suggest that using modern controls on the circulators such as the time / temperature or Auto Adapt which result in intermittent flow around the domestic circuit would be fine as this is nothing less than what the flow or indeed the heating system is exposed to piped using the same material.

Thoughts please ?

 

[ShaunCorbs]

I have read a few bits of info on this & each has stated that plastic is not suitable for "continuously operated" secondary returns as it has not been tested for this inline with the manufacturing BS's.

However I would suggest that using modern controls on the circulators such as the time / temperature or Auto Adapt which result in intermittent flow around the domestic circuit would be fine as this is nothing less than what the flow or indeed the heating system is exposed to piped using the same material.

Thoughts please ?

In theory yes would be OK but what happens when the cus or the next eng comes and puts it on most of the time,

And can't see the use of temp sensors as more to go wrong

 

[PhoenixServices]

I thought that as well Chris but still voids the manufacturers warranty, was reading it earlier on polypipe website. Just means it is going to cost a fortune to be in line with water regs/ vaguely usable.

 

[chris watkins]

Have you thought of using self regulating heat tape instead of a return ? It is what I use to use before these modern pumps & controls came long.

HWAT-T55

Raychem trace heating for DHW complies with latest industry standard - Modern Building Services

You use to be able to get it through Pipe Line Centres
(sorry Ray I will go wash my mouth out straight away)

 

[ShaunCorbs]

Have you thought of using self regulating heat tape instead of a return ? It is what I use to use before these modern pumps & controls came long.

HWAT-T55

Raychem trace heating for DHW complies with latest industry standard - Modern Building Services

You use to be able to get it through Pipe Line Centres
(sorry Ray I will go wash my mouth out straight away)

you used it with success, the only problem i see is when the wire goes/ develops a fault you either need to rip the floor up or put a hsrc in

 

[chris watkins]

ooo we are being rather negative tonight Shaun. Do they install anything new in Wales?

 

[ShaunCorbs]

ooo we are being rather negative tonight Shaun. Do they install anything new in Wales?

naa just thinking of all angles and all possibilities

 

[PhoenixServices]

Priced it for mclp and a press gun. Which I have wanted anyway. Only one cylinder. 1 bathroom and 1 shower room. Downstairs loo and kitchen sink and 2 utility rooms

 

[Staffy85]

tectite make MLCP in 15mm and 22mm, price isn't that bad, you only need there hand calibrating tool which is around £20-30 and there liners,,