Lockshild on the flow or return?

[Mr Spoons]

Hi,

I am replacing my rad with a towel rad, and am just wondering if it matters which way around the lockshild and TRV go with respect to the flow and return on a 10mm microbore system (which ISTR have a indvidual flow and return for each rad?)

I can think of any reason why it would, but stranger things have been known... It just so happens that the way the towel rad mounts, it would be more convenient to have the TRV on the opposite side from what it used to be, and I'd rather not have the hassle of swapping oer the flow and return.

Cheers, Chris

[TheScullster]

"Mr Spoons" wrote

The usual consideration is whether the TRV can handle "reverse" flow. Initially, TRVs were unidirectional and would suffer from noisy and eratic behaviour if installed incorrectly. Many valves now claim to be bidirectional, but purists will argue that mechanically they are likely to perform and wear better if installed on the flow side. The above is based on standard 15mm flow/return systems but I would suspect applies also to 10mm (I thought microbore was smaller - 6mm?)

Phil

[fred]

In article , TheScullster writes

That's certainly my view, bear in mind it's flow side if vertical, return side if horizontal.

[Lobster]

Could you explain that last bit?

David

[Lurch]

On Mon, 12 Feb 2007 19:55:27 GMT, Lobster mused:

Orientation of the valve depending on direction of flow through it?

[fred]

Sure, with the orientation as described the flow pushes so as to lift the sealing washer off its seat and as the TRV reaches its set temperature I think it will close off more smoothly. If it is the other way round then the flow may tend to close the valve artificially at close-off resulting in chattering (oscillation). I had chattering on one rad in a system with a high head and this was what I suspected was happening.

[robert]

The other factor to consider is whether the TRV would be in a more appropriate position regards room temperature if installed on one side rather than the other.

I would avoid having the TRV tight in a corner or next to a draughty door.

I have been told that having the feed on the left and the return on the right of a rad is considered "good practice". Robert

[<me9]

Not so with most modern ones. 10 years ago perhaps. the last few I've fitted (Honeywell) have been ok both ways round. Personally I'd always fit them horizontally (and on the outlet) for better temperature regulation, but most will work at either end, horizontal or vertical.

[TheScullster]

wrote

You haven't been to plumb centre and fallen for the old "take this one it's a left handed radiator" routine I hope!

[robert]

I avoid Plumb Centre! No seriously a plumber doing some work for/with me suggested that leftside flow was "accepted practice" at least in the olden days, and that sticking to a system on all jobs was a good idea. Another comment was leave all slotted screwheads lined up with slots vertical . Robert

[Guy King]

The message from [e-mail] contains these words:

Nah, that never looks as nice as a smartly saluting 45°.

[Stuart B]

Would that be top left to right bottom or top right to left bottom .?