Plumbing advice please

[Deleted member 65149]

I’m going to replace the existing standard radiator in our family bathroom with a wider and taller heated towel rail. The heating system is sealed and all the radiators are fed by 10mm Speedfit pipe coming out of the walls at central positions behind the radiators. I’m going to fit the towel rail with angled fittings to allow the pipe work to go straight into the stud partition wall (via a TRV and lock shield valve of course).

My question is, do I need to drain down the whole system as everywhere on t’Internet suggests? I’m guessing that all that advice is for good old-fashioned vented systems with header tanks and 15/22mm copper. Surely I can get away with completely shutting off all the rads at the same level and above the bathroom, then releasing the pressure on the system. In that way I’m hoping there’ll be very little water to drain off before taking off the bathroom rad and putting in a bit of new Speedfit. Does this sound ok? Also, since I’ll only be taking away a radiator full and a bit of water I’m guessing I won’t need to top up the inhibitor?

Thanks

 

[Will]

Sounds good to me, you can drain from the old radiator anyway once you’ve shut down as much as you can to just remove as much as needed. Once it’s stopped leaking out - fit the new one and sort your pipe connections/valves out, then just top the system pressure back up and bleed the new one as usual. The amount of inhibitor lost is surely going to be minimal (5/10% tops?) so I doubt it would make any odds - I doubt plumbers use an exact amount of inhibitor fluid for the system capacity, more a one size fits all container is dumped in and left

 

[Deleted member 113659]

Just be aware that replacing a standard panel radiator for a towel radiator is going to give less heat to the room. The BTU’s on towel rads (especially chrome) are considerably lower. (Unless the rad you’re removing is a tiny single one).

Then you’re going to fill new towel rad with towels which will further ‘muffle’ the heat.

 

[clk208]

Just be aware that replacing a standard panel radiator for a towel radiator is going to give less heat to the room. The BTU’s on towel rads (especially chrome) are considerably lower. (Unless the rad you’re removing is a tiny single one).

Then your going to fill new towel rad with towels which will further ‘muffle’ the heat.

Yep surprising how little heat the towel rads put out, even the bigger ones.

Previous owners of our house did this in one of the bathrooms making it pretty much unusable in winter ever with heating on 24/7.

 

[Deleted member 65149]

Just be aware that replacing a standard panel radiator for a towel radiator is going to give less heat to the room. The BTU’s on towel rads (especially chrome) are considerably lower. (Unless the rad you’re removing is a tiny single one).

Then your going to fill new towel rad with towels which will further ‘muffle’ the heat.

Thanks Ant. I took all that into account and bought a towel rad with a slightly higher BTU rating than the existing rad, which was more than capable of keeping the bathroom toasty. I'm going from a 700mm x 400mm double to a 1200mm x 600mm towel rad with nice chunky 25mm bars.

Incidentally, I bought the new rad online from Trade Radiators who've been fantastic. They mistakenly sent the wrong rad yesterday so I asked for a replacement using their online form. The right one arrived this morning. (They haven't yet asked me to send the other one back!)

 

[Deleted member 65149]

Yep surprising how little heat the towel rads put out, even the bigger ones.

Previous owners of our house did this in one of the bathrooms making it pretty much unusable in winter ever with heating on 24/7.

The one we have in our en-suite is only 1000mm x 600mm but it chucks out lots of heat, even with two towels on it. And that's with two external walls and the loft directly above.

 

[clk320x]

Just be aware that replacing a standard panel radiator for a towel radiator is going to give less heat to the room. The BTU’s on towel rads (especially chrome) are considerably lower. (Unless the rad you’re removing is a tiny single one).

Then you’re going to fill new towel rad with towels which will further ‘muffle’ the heat.

Someone’s a professional

 

[zipdip]

Well I cannot see any problems with what you want to do,I only suggest you make certain where the studs are to fix the rad too,as most of these towel rads need to be fixed between the ribs of the rad.

 

[Deleted member 113659]

Someone’s a professional

I’m sure someone will be along soon to say otherwise.

 

[moog999]

And they are feckin useless in warmer weather. So their towel drying function drops to nil.

They allway seem to rust like buggery at the valve connections too....don't buy a cheap one.

 

[Deleted member 113659]

And they are feckin useless in warmer weather.

That depends on how through the fitter is and if he/she has bothered to fit an element.

 

[Railwayman]

Just to add my 2 pence worth, have been installing heating systems for many years (DIY, friends and family) and as Happytalk points out these towel rads never put out the stated BTU output, indeed have been replacing them for folks on a regular basis. You can get integrated panels (towel / rad) which perform much better. As for inhibitor, never hurts to top it up.

 

[Piff]

In old house I fitted an 1800 x 600 one with open feed (no TRV). Room was steaming hot and very soon had to fit a TRV.
In current house with a fancy air source heat pump system, we have underfloor heating with open flow in the bathrooms. We also have 1200 x 600 towel rail rads in the bathrooms run off an additional coil in the hot water cylinder, with pump controlled by a pipe stat & a time clock. So when underfloor heating shuts down we still have the towel rail rads running to keep towels toasty.
I always use the white towel rails rather than chrome for the better heat output.

 

[Deleted member 113659]

That depends on how thorough the fitter is and if he/she has bothered to fit an element.

 

[Chugg]

I think most has been answered for you, yes turn all rads off (beware of leakey glands if not operated for a while) and just drain to the level you need, same with unvented or vented (pipe size/material irrelevant) arguably easier on old vented as bung the open vent with a carrot/parsnip or rubber bung if your posh, and at the outlet at bottom of F&E tank to suspend the water in the system (then drain down anyway after you flood the house!)
I agree electric element is also good for summer (will need part p person for wiring).
Also agree with happytalk73, some of the published btu figures are on par with mpg figures for comedy wild claims. Towel rails are ok for warming towels, not too great at heating rooms. You could size correctly using Mears wheel/calculator and then over size to account for the heat restriction of the towels covering as a fudge factor (depending on room size/factors, it might take up a full wall!), but as railwayman says the panel/traditional rad rails are the best bet for room heat and towel warming if that’s the aim, but pricier.
Also also agree a bit more inhibitor is better than a bit less (leave air vent or blank off the rail, when all fitted up just funnel some into the rail and fit the vent/blank then open rad valves and fill ‘er up!). Actually Will, I would measure inhibitor as accurately as poss, you don’t want to give away more than you need too, plumbers are notoriously tight!

As for TRV and lockshield, you don’t usually fit them to towel rails (that’s not to say you can’t if you wish) as if someone is having a hot steamy shower/a towel covers it/or the ambient room temp reaches target etc, they close off leaving the towel rail to cool (unless leccy element is fitted and switched on as back up)
TRV’s are for regulating room temperature, not deciding if you want warm towels or not!
And they look a bit uneven/clunky.

Rambled on a bit there, didn’t I?

 

[Darrell]

We don’t put TRV’s on a towel rail therefore using it as the bypass.

 

[Deleted member 65149]

Thanks guys, especially all the details from Chugg.

I wish I’d asked the questions before buying the bits. My decision on what to buy was based on the towel rad I bought to go into our ensuite when I had it completely refurbished. That towel rad always heats the ensuite perfectly well, even with it always having two towels draped over it. Our family bathroom is about the same size as the ensuite, being directly below it, but I played it safe by buying a slightly taller rad. Even though I didn’t get a TRV for the ensuite rad, I bought one for the bathroom - just coz I thought it would be a good idea. Now I’m wondering whether or not to bother with it. I probably will.

 

[Chugg]

We don’t put TRV’s on a towel rail therefore using it as the bypass.

Tru dat Darrell on old systems but not necessary on new systems as new water heaters (boilers) have an automatic bypass inside, but is a back up if the auto bypass fails. If you are using a rad/rail as the only bypass on a retro fit pumped system it’s best to lockshield them so cant be shut in error, slight downside is that rad/rail will always be on when CH is on whether you want or not. Or fit an auto bypass valve.You should have a rad with no TRV’s in the same area as your room stat anyway, usually hallway (TRV’s and room stats can conflict) which acts as a back up bypass.
All that no TRV’s in same area as room stas now has a ? over it these days what with wireless portable room stats cos it could be on your table next to you while you’re warm and cosy watching TV in the living room with the log burner on so not calling while the rest of the house goes cool.

 

[Chugg]

Thanks guys, especially all the details from Chugg

A pleasure. Hope it all goes ok bud, I’m sure it will.

 

[Deleted member 113659]

Tru dat Darrell on old systems but not necessary on new systems as new water heaters (boilers) have an automatic bypass inside, but is a back up if the auto bypass fails. If you are using a rad/rail as the only bypass on a retro fit pumped system it’s best to lockshield them so cant be shut in error, slight downside is that rad/rail will always be on when CH is on whether you want or not. Or fit an auto bypass valve.You should have a rad with no TRV’s in the same area as your room stat anyway, usually hallway (TRV’s and room stats can conflict) which acts as a back up bypass.
All that no TRV’s in same area as room stas now has a ? over it these days what with wireless portable room stats cos it could be on your table next to you while you’re warm and cosy watching TV in the living room with the log burner on so not calling while the rest of the house goes cool.

Are you a joiner then?