Table of Contents
IntroductionI am trying to give an overview of the plumbing choices that we made. I am sure that there are many aspects to consider which I may not be aware of as we did not encounter them. Plumbing items are fairly standard and their features are well understood. You need to decide which system you want to install - solar water heater, pressure pump, etc. - and the choice itself is not too difficult. But you have to be careful about supervision and make sure that the vendors deliver what they promise. Also multiple systems need to work with each other so you need to plan that the laborers come and work together to make sure that everything works, otherwise things will just fall between the cracks.
External and Internal PipingThere are two main choices for both internal and external piping; their costs are very comparable so you should really pick the one that meets your needs the best.
One more option for external piping, recommended by some solar water heater vendors are Kitec pipes. I have heard that these pipes have had major problems in North America but I do not know whether these problems are related to local weather. We just used CPVC pipes for external piping too.
- GI pipes: These are galvanized iron metal pipes which have long been the industry standard. They are durable; especially in internal piping; if you end up drilling on the overlaid tiles, there is little chance that the internal GI pipes will get damaged. However, they tend to get rusted over time so the external pipes look bad, and the internal pipes reduce the flow of water due to rust accumulation inside.
- CPVC pipes: These are plastic pipes which are slowly being adopted much more. They are slightly cheaper and easier to install. Once installed properly with no leakages, they are very durable and last a long time. They do not have the rusting problem as GI pipes. However its easier to damage these pipes, e.g. while drilling for accessories in the bathroom, and then fixing them is a big problem resulting in a lot of civil work. We installed CPVC pipes so we took photos of all internal piping to ensure that we do not damage them in case of external drilling.
One more option for internal piping is a new European system called PEX. The basic idea is that there is a single pipe distribution box located in your bathroom and all pipes start from this box. The pipes are flexible plastic pipes. If there is any problem with a pipe, you can pull out the entire pipe from the distribution box and replace it with another pipe without having to remove any tiles. In order to install this system, some special hardware is required which is provided at the time of installation. It has been in the market for about 10 years but it is yet to catch on. It is about 15-20% more expensive than CPVC or GI piping. Most likely it is the future of plumbing but plumbers are still unaware of it so all installation and maintenance has to be done via their service center itself. Their Pune office is located opposite the Telephone Shoppe on Apte Road.
Vendors: GI and CPVC pipes are available in various diameter sizes and lengths at any hardware store. In Pune, there is a wholesale merchant called Mangaldas Venichand located in the same building as Sanghar Ceramics right at the beginning of Bibwewadi Road. You can get significant discounts if you get large orders from them.
Solar Water HeaterWe installed a 200 liter solar water heater from Racold for our small 3-member family. The vendor told us that the main problem with the heater is in monsoon; summers and winters have enough sunlight to give enough hot water. So we also installed an electrical backup for such rainy days. Some of the other brands that we considered included Tata BP, Bipsun, Kaushal, Bosch, and SaveMax. Some of these are local manufacturers and some are branded names; the cost difference was around 10% more to get a branded system. You get a government subsidy to install a solar water heater which reduces the cost of the system a little bit.
Tank System: There are two types of solar water heaters - a single-tank system or a dual-tank system. When hot water is used from the tank, cold water replaces it. To avoid mixing the water and effectively reducing the water temperature, you can use a dual-tank system. The hot water collects in one tank, and the heated cold water from the other tank replenishes the water used from the first tank. Buffering the hot water helps to maintain the heat. Note that the cost almost doubles with any dual-tank system.
Pressure Pump: If you plan to install a pressure pump, you need a pressurized tank which will cost much more than the regular tank.
Storage tank: Most people will get an extra storage tank for water, especially in a bungalow or if you want your own water storage when the society tank water runs out. You will have to account for installing the tank and an extra stand to hold the tank, as it will need some head to feed water into the solar water heater tanks.
Piping: New hot water piping will have to be installed to all points in your house where you want the heated water. Hot water piping can be done with GI pipes, CPVC pipes, or Kitec pipes. It was hard to judge which one works better in the long run. Similarly, cold water piping may also need to be installed if you add a storage water tank.
Here is a rough idea of the basic costs involved in installing a dual-tank solar water heater (about 200-250 liters):
Solar Water Heater Costs Item Cost Non-Pressurized tank Rs. 45,000 Pressurized tank Rs. 65,000 Cold water piping Rs. 1500-2000 (just for the heater)
More if you install a tank, on per running foot basis
Hot water piping Rs. 100-150/r.ft. Electrical backup Rs. 1500-2000 Labor, Transport, Valves, etc. Rs. 1000-3000 Storage Tank Rs. 5/liter Fabrication stand for tank Rs. 3000-5000
Pressure PumpAll your bathroom fittings will be chosen based on the amount of water pressure in your pipes. If you live in a multi-storey building on a lower floor and the tank is located at the top of the building, you will get good force and do not need a pressure pump. In a bungalow or a flat located towards the top floor of a building, a pressure pump will surely help to boost the water force. We have a duplex flat - 3rd and 4th floors - in a 4-storey building. The society tank and our personal tank are just above our 4th floor bathroom so we get almost no head for good water pressure. We decided to install a pressure pump. Figuring out the exact configuration of the pressure pump, our own tank in combination with the society tank, extra valves, and the solar water heater took some work. We installed a rain shower in one bathroom so a pressure pump was almost a must to enjoy it. We also had to redo cold water piping to our bathrooms due to the pressure pump. We considered a few brands such as KSB and Kirloskar, and finally went with Grundfos model CM 3-4. The 0.5KW and 0.7HP pump with a 24-liter pressure tank cost around Rs. 35,000, and cold water piping cost around Rs. 10,000. Installing the pump and other hardware cost about Rs. 5000. After having lived in our house for a few weeks now, we really did not need a pressure pump except for the rain shower.
WaterproofingThe less said about waterproofing, the better it is :). Find a person who will give a guarantee (in years) for the work he does, otherwise its not clear what will work and what will not. The one rule is - if its not broken, don't fix it! We did not change our terrace tiles even though they were a bit dated because of the fear of causing new waterproofing issues. And get a few comparison quotes because the rates vary quite a bit. Waterproofing is best done in the summer before the monsoon or just after the monsoon so you know exactly what needs to be fixed.