The direct system is used in frost-free locations where the ambient temperature never falls below 5ºC and where the water quality is good (less than 600ppm Total Dissolved Solids/Minerals).
The solarfit conversion kit direct system is used in conjunction with an existing installed Kwikot domestic electric water heater, which is installed inside the roof (Split System) and without an integrated heat exchanger. The water from the electric water heater is circulated through the solar vacuum tubes by means of a 12V solar circulating pump (pump circulating method), transferring solar energy into the electric water heater and heating the water directly.
The Kwikot Kwiksol Solarfit Conversion Kit Direct System has been specifically designed to convert the following Kwikot high pressure electric water heater models to a solar system:
The conversion kit includes a new heating element and Kwiktherm Thermostat.
(A comprehensive instruction and installation manual is supplied with the purchase of the Solarfit Conversion Kit Direct System)
The existing flange assembly behind the electric plastic cover is unscrewed from the inner storage tank of the electric water heater and replaced with a purpose made flange including water distributor pipes, new element and thermostat, called a Solarfit Direct Flange Assembly.
The short cold water pipe on the Solarfit Flange Assembly must face downwards into the tank and the longer, hot water pipe points upwards in the tank.
The solar vacuum tubes and 12V photovoltaic solar collector are installed outside on the roof with a north facing orientation and inclined as close to 30 degrees from the horizontal as possible.
A 15mm copper pipe is fitted between the solar vacuum tubes and the new Solarfit Direct Flange Assembly to allow the water to circulate between the electric water heater and the solar vacuum tubes.
The 12V solar pump is installed between the solar vacuum tubes and electric water heater (cold side) to ensure positive flow. The pump is powered by a 12V photovoltaic solar collector.
The warranty period on the Kwikot solarfit conversion kit (new parts) is one year from the date of installation providing that documented proof of installation is furnished. On existing parts the balance of the original warranty of the Kwikot Electric Water Heater will apply. The installation must be carried out by a Kwikot Approved Installer, failing this the warranty will become void.
Roof location and Pitch
The solar vacuum tubes are to be installed in a parallel array and at an angle determined by the latitude of the installation.
For optimum performance the solar vacuum tubes need to face the equator (facing north for southern hemisphere installations). Installation on angles of up to 45 degrees away from the equator do not have a major effect on the annual solar output, consequently roof locations which face less than 45 degrees away from the equator are acceptable. Solar radiance from the sun begins at about 10:00 until about 16:00 and is at its peak between 12:00 and 14:00.
If the solar vacuum tubes are installed with an east facing bias, the best solar capture is achieved in the morning, and if the installed with west facing biased, in the afternoon.
The location should not be subject to excessive shading from trees and adjacent buildings and particularly between 9:00 and 15:00. Remember that shadows are longer in winter than in summer so a location that is free of shadows in the summer may have some shadows in winter.
The solar vacuum tubes should be installed on a roof pitch greater than 8 degrees and less than 30 degrees. Where the roof pitch is greater than 30 degrees, the installation will require additional support to prevent it from moving downwards when installing and after installing. If the roof pitch is less than 8 degrees the installation will require a mounting frame to increase the pitch to above 8 degrees.
The solar vacuum tubes have a comprehensive 5 year warranty from date of installation and subject to the following conditions: