dual fuel towel radiator questions

Hi

I am not a plumber nor experienced diyer and have some questions about ladder dual fuel radiators. The WWW seems to be a bit lacking..

1) I was wondering how you choose your element wattage? Is it based on rad height vs element length or rad wattage vs element wattage?

2) there is discussion about how to switch between gch and electric use that tells you to switch off flow for electric and switch on for gch.

There seems to contention between advice what to do with the return valve ranging from keeping it full or slightly open to relieve pressure build up. One site even said just open the bleed valve slightly to relieve pressure instead.

I was wondering what you would advise here and is the advice the same for a rad fitted with a TRV and lock shield?

3) what are the practical and safety implications of not doing the switch correctly resulting in the following scenarios?

a. If you run the element with the flow open and the gch isn't on.

B. If you run the element with the flow open and the gch is on

C. If you run the gch having forgot to open the flow?

Many thanks in advance for any advice.

N

I have put a separate electric one in. I had wall space I got one with a t/stat, so we can keep it on all year at a low setting.
I did look at putting an element in the c/h one, but couldn't ar$$ed to keep switching.

just go for an electric one... can be as low as 35w...all you need for towels...

The wattage is very low as is the water content so you don't need to do anything, other than switch the heater on when the gch is off.

when the gch is on the temperature in the rail will be higher than the stat so the heater will be off all the time the gch is circulating

doitall said:

The wattage is very low as is the water content so you don't need to do anything, other than switch the heater on when the gch is off.

when the gch is on the temperature in the rail will be higher than the stat so the heater will be off all the time the gch is circulating

Click to expand...

So never any need to fiddle with values or worry about pressure?

Nope, if there was they'd have to be fitted with a PRV for safety

doitall said:

Nope, if there was they'd have to be fitted with a PRV for safety

Click to expand...

Interesting ...point 5 at
http://www.geyser.co.uk/-i-24.html seems to suggest you do.

Cheers

Manufacturers instructions most always be followed, including shopping around for something better built.

Turning one end off can prevent unwanted circulation however unlikely because of the low temperature.

However if they/you are intending to use something like a 1kw immersion type heater, I would be very worried without built in safety devices.