Insulating hot water tank with spray foam?

stevanbt

Hi all,
We have a hot water tank that has been insulated with foam spray by the manufacturers. However, there are a number of areas of insulation missing (the installers had to remove these to get the tank into the cupboard).

What would be the best way for me to re-insulate these parts of the tank? I was thinking that I would be able to use something like expanding foam. Can i use any expanding foam or are there specific ones? The tank is tight against two walls so I can't tie an old fashioned jacket to the tank.

Thanks in advance, Steve.

TimBuckTeeth

Expanding foam should be OK. Check the maximum working temperature of the foam, would need to be at least 70C.
It would be a good idea to use fire rated foam, just incase of any problems with the immersion heater wiring.

The expanding foam I have used in the past falls off vertical surfaces (like the side of the tank) until starting to set. A piece of fairly thin plastic could be used as a temporary mould, eg. cut up a lemonade bottle to give a sheet of plastic, cut a small hole in the centre for the foam nozzle to go through. Then use gaffer tape to seal the edges of the plastic and fix it over the area on the tank, then spray the foam through the hole, leaving a bit of space for the foam to expand. You might need to cut the plastic off after the foam is set, but it should keep it where it needs to be.
It is very messy stuff and virtually impossible to remove from carpets etc. I usually wear disposable latex gloves. A can is only good for one session, if left for a few minutes the foam sets inside the valve and nozzle. So prepare every thing first and use newspapers to cover stuff.

[Deleted User]

TimBuckTeeth wrote: »

Expanding foam should be OK.

Hi,

great explanation on how to set up a temporary mould.

Like your username and location Tim, my first laugh of the day, :rotfl:cheers, Timbuckshee, :rotfl: