THE cold water tank usually situated in the roof space should be protected against dust and dirt by a wooden cover on top. This cover should not come close down on to the top of the tank, but be spaced from it by battens nailed on underneath, so that an air space of about an inch is left between the under side of the cover and the flange of the tank. Plywood is recommended as a material which requires little preparation. The cover should have a framing all round the edge, and this frame should be halved together at the corner joints. Cut some lengths of batten, about 12 in. wide by 1 in. thick, and cut two pieces exactly the length of one side of the cover; the remaining two are to be the length of the width of the frame cover. Two screws are put through at each joint, and the plywood is nailed to the frame by ¾ in. round wire nails, or small screws may be used. The cover is to go on so that the flush side is uppermost. Now for the battens to raise the cover and leave an air space; screw two pieces of the [fin. Batten to the under side, flush with the flange of the tank. These directions assume that the inlet cock goes through the side of the tank, which is a good arrangement; sometimes, however, the rising main is brought up so that the inlet pipe goes over the top of the tank, and in such a case the wooden cover would have to be cut around the pipe.
Access to the Tank
Floorboards should be nailed to the joists in order to provide a safe track from the trapdoor over to the tank, which often is placed some distance away, near one of the outside house walls. Other boards should be fixed around the tank on the side where any maintenance work will be done. The use of loose boarding is inadvisable and invites accident.
It is a good investment to have a proper electric light point run to the tank loft, with a switch near the trapdoor. But this is not a job for the amateur. It is dangerous to use a trailing flexible connection to a lamp holder on the landing below. Few trailing flexible cables, after a period of service, are absolutely safe against leakage; if the worker inadvertently grasps part of the tank, or the water pipe, with one hand, and perhaps touches the flexible cable or the lamp holder with some other bare part of the body, a dangerous or fatal shock may result. A proper inspection lamp, with heavy insulation, can, of course, be used with reasonable safety, but a permanent lighting point is to be preferred. In frosty weather the properly fixed lamp may be left alight at night, and its continuous gentle warmth may prevent freezing.
Ball Float Valve
New washers are fitted in the same manner as for a flushing cistern. Since access is more difficult, make sure that a proper job is made of the washer replacement, and that spare washers are at hand. General precautions against frost are described elsewhere in this website, but one good method of protecting the incoming main pipe may well be mentioned here. Usually this pipe runs up vertically from the room below (generally the kitchen), and is left bare for the distance between the lower ceiling and the tank. Make a wooden casing with three sides, to encase the pipe against the wall. The diameter of the pipe will determine the dimensions of the case, and the wood need not be thicker than ¾ in. If the diameter of the pipe is 1 in. allow an extra iin. On the depth and width of the case. The casing encloses the pipe, being fitted on from the front,-and is fastened to the wall by about two holdfasts at each side.
Drive wooden plugs, at suitable places, into the brickwork joints, and then knock in the holdfasts so that the flat top comes against the side of the casing. There is a hole in the holdfast for inserting a screw into woodwork. The casing should go down close to the laths of the ceiling below, but should not impose any weight on them. After fixing the contrivance, fill it from the top with dry sawdust, which can be shovelled in around the pipe with a garden trowel. The hooks, etc. which hold the pipe to the wall should be loosened, and pieces of ¾ in. batten put behind the pipe. The idea is to surround the pipe with the insulating material, so that some gets behind as well as on the other sides.
A better but more elaborate way of constructing this insulating tube is to make a board to fit behind the full length of the pipe, and to fasten the pipe to the board with proper clips secured by screws. Make the casing so that it will fit over the board, which means that the width of the board must be the same as the inside width of the case, a loose fit. The casing can then be fastened on by about two screws at either side, these screws going through the sides of the casing and into the edges of the board. Fill in with dry sawdust as explained above. Any short horizontal portion of pipe may be lagged with strips of felt wound around it and secured by string.
Do not put an oil lamp in the tank loft to warm this space in frosty weather. No oil lamp or stove is trustworthy enough to be left for hours unattended. Instead, open the trapdoor, and let the warmth from the rest of the house circulate above. When attempting to thaw frozen pipes in the roof space, do not use a blowlamp; usually it is the ball valve that gets frozen, and this can be thawed in many cases by pouring boiling water over.it. Sometimes the ball gets trapped by ice formed on top of the water in the tank. Break the ice around the ball and lever, and use boiling water for the rest. In any case, the blowlamp method should be left to a plumber. Apart from the danger of fire, the amateur may melt or weaken the lead pipes.
Hot Water Vent Pipe
In many houses which are provided with a domestic boiler, a pipe will be found at the side of the cold water storage tank, the pipe standing up some distance and having its end turned down over the tank. This pipe is to vent the hot water system in the event of pressure developing. On occasion, some water may be forced up this pipe, which is why its end is turned down and brought over the open cold water tank. Obviously, if we close in the top of the tank, any water that comes out of the vent will splash over and prove a nuisance. Nothing must be done to alter the height of the vent pipe, which provides a safety valve, or to obstruct its open end. The best thing to do is to cut a fairly large round hole in the wooden cover, immediately below the outlet of the vent pipe. If the level of the water in the tank rises above the safe level due to a faulty inlet valve or ball float, deal with the defect.