Abstract: A multi-cylinder reciprocating compressor is automatically staged at low ambient temperature to improve refrigerant volume flow while facilitating subcooler operation and return of vaporized refrigerant from the subcooler to the inlet of the second stage cylinders of the compressor in the two stage mode. A solar evaporator substitutes for the outdoor coil when the solar heated storage tank temperature exceeds that of ambient. During staging mode, the wrist pins of the low side cylinders and the high side cylinder undergo proper load reversals, since intermediate suction pressure is applied to the wrist pin of the high side cylinders.

Abstract: An epoxy resin aqueous composition of the room-temperature hardening type having improved rust preventive, anti-corrosive and weatherproof properties, which comprises an aqueous dispersion containingA. an epoxy resin having at least two epoxy groups per molecule, andB. a condensation product prepared by condensingI. a polyamine mixture of 4-aminomethyl-octamethylene-diamine and a polyalkylenepolyamine represented by the general formula (III)h.sub.2 n -- r -- nh -- (rnh).sub.n -- H (III)wherein R is a straight-chain alkylene group having 2 to 4 carbon atoms and n is 0 or an integer of 1 to 6, withIi. a reaction product ofA. an .alpha.,.beta. -unsaturated carboxylic acid or an ester thereof represented by the following general formula (I) or (II)y -- ch = cx -- y (i)y -- c .tbd.