Sunday 6 December 2015


In follow-up comments to my post about winterising Erin Mae, Halfie expressed surprised at my statement that the boat's calorifier is not lagged. Which got me thinking and googling. I found that one chandlers describes its calorifiers as having 25mm of polyurethane foam insulation, inside the shiny blue exterior.

I don't think I even considered internal insulation when I wrote my comment, which is odd because the hot water tank in our house certainly has it. But I suppose most modern calorifiers must be constructed this way – I just hadn't thought about it when it was installed. I have memories of houses from decades ago having separate lagging jackets needing to be tied in position, and that was what was in my mind. On Erin Mae, water heated the night before does indeed stay warm enough for a morning shower, so I guess the calorifier must be insulated. Obviously my analysis lagged behind the reality.

Do any of my readers use external lagging?

1 comment:

  1. Hi Martin, Last year when we winterised the boat, we put a blanket over the calorifier (as much of it as we could get at, given it rests on the floor under a dinette seat and extends back into a gap between the washing machine and fridge in the kitchen. This year tho, Steve at Debdale told us not to bother as the calorifier is insulated and we have two greenhouse heaters on board to keep the temperature above zero.
    As a matter of interest, we fitted a new gas hot water cylinder in our house late last year, and the guy who did the work told us that all cylinders are insulated these days - hence hot water cupboards are not quite so effective at airing damp washing!
    Cheers, Marilyn