Marquee heating dilemma

[louise73]

Hoping for some friendly advice please. We are supplying a marquee for a customer on Christmas day and of course due to the weather they have asked for heaters. Its a small marquee so the normal indirect diesel heaters not feasible in this case. We have a range of 2-3kw heaters and the marquee is very small, only 9m x 3m. However the last couple of times we supplied these heaters there seemed to be issues with fuses blowing etc. Now I have a limited knowledge of electrics, but I thought my sums were correct in that 1 heater 3kw could sufficiently be powered by a 13amp plug so as long as all heaters used were in separate plugs then that would be ok?

is it wise to use RCD's in the socket? I have heard that these can be very sensitive and may cause problems?

Any advice to put my mind to rest that would be great. Thanks

 

[telectrix]

basically, look at the consumer unit in the house. if you have RCDs there, ( like a wide circuit breaker with a test button, and should have a label stating that the installation , or part of it, is RCD protected, then look at the breaker labels. you may find the there are more than one socket circuit, e.g. sockets down, sockets up, sockets kitchen. take your heater extension leads one or at most two, from each circuit.

 

[Mr.Si]

Louise - the issue of damp isn't about where the sockets and connections are, it's about the way the actual heaters work. When you turn them on in the morning, they will be physically sucking damp air in one and out the other. Moisture can and does settle on the heating elements inside them, effectively causing enough of a 'short' to trip a sensitive RCD until such time as the damp dries out.

To the sparks - I've seen on more than one occasion a very large professional marquee literally dry out when watching an RCM across the incomers; over-ride the actual trip and watch the numbers slowly fall from sometimes even amps worth of leakage down to 'normal' figures after about an hour - just caused solely by damp air overnight.

And for similar reasons, when I used to provide PA Systems for Marqueed events, the advice was always to leave the amps on and just turn them down, so they were on and keeping from Damp, but not likely to allow the speakers to make noise. It's all about the damp proofing!

 

[cook1e]

Have you calculated the heat input required for your marquee ? based on the size my guestimate is about 18 - 20 Kw of heating, depending on the level of heat required. and it is only a guestimate, you would need to take into account the outside temperature, the insulation value of the marquee and many other factors

good luck

 

[GLENNSPARK]

And Louise, if/when you find that you have RCD protection for the outlets to be used....be sure to press the manual test button on the RCD itself when everything is ready to go.....just to prove that it will let go if a fault occurs wont you......