What is Solar Thermal?
Solar thermal is water that is heated by the sun. This heated water can then be used to heat water in a water heater, heat air for forced air heat, or heat water for radiant heat. Panels are placed on a south or west facing roof, these panels have liquid that flows through them. This liquid (water, glycol or in older system, oil) is heated and then recirculated to a holding tank and used to heat the coil in a your hot water tank or warm the air in your furnace or preheat the water in your boiler.
I have an existing solar hot water system how do I properly maintain it and how do I tell if it is malfunctioning?
The first check you can make is to feel the solar storage tank pipes where they connect to the top of the tank – carefully – they could be hot or should be at least warm by the end of a sunny day. There should be pipe insulation over the pipes and you will have to remove a little or slide it out of the way. Almost all solar heating controllers give an indication of when they are in heat collecting mode. Observe the lights or display (if you have one) on the controller to determine when it is giving an output to run the collector loop pump. If this is not evident, we may be able to guide you. (see more details below) Please contact us with your questions.
I need to have my roof replaced and I have solar panels, what do I need to know?
If you are having your roof replaced and you have solar panels, please read this important information first:
I bought a home with a solar thermal system, what do I do with it?
If your system isn’t running or if no one gave you instructions on how to operate it, the best investment you can make is to get a solar analysis. This is a complete checkup of your system (and we’ll walk you through how to operate it as well), with every item checked to make sure it is working properly and if any repairs are needed. With just a small investment, your existing system can save you 75-90% on your gas bill yearly.
Contact us with any questions or call for your free site visit.
MORE ON SOLAR THERMAL FUNCTION AND REPAIR:
From Steve Ruby, Owner of Aqua Care Solar. Steve has 30 years experience in Solar Thermal installation and service:
How to know when a Solar Heating System is working:
Since the goal is to heat something, have a look at the following:
- If the system uses air to move heat, is hot air coming through or from the duct?
- If the system uses water to move heat, is the tank or heated object hotter than the surrounding temperature? Solar storage tanks should be hot at the end of a clear day – assuming no large amount of heat has been withdrawn.
- If you have a controller with a read out, it will tell you with a few pushes of a button. A blank display is a bad sign.
- Small pumps – when running – are normally on the lower end of hot. A pump that is scalding hot – so hot that the paint is about to peel off – is not circulating and needs maintenance.
- Check for heat flow. Pipe temperatures can be tested (or felt) to check for heat flow. Any pipe could be very hot so use caution when touching one. Antifreeze systems that loose pressure can and will become air locked. The pump(s) will run and seem to be working (hot and humming) but the tank will be cold. A pipe attached to a running air locked or stuck pump will be hot, so don’t be fooled. Feel a pipe up stream, or below, or some distance away from a pump that is running for accurate pipe temperature. The line could be air locked, or the pump could be stuck. No heat flow in a Drainback type system might indicate low water or a bad pump in the system.
Antifreeze systems need 20 lbs pressure or more to run correctly. Old gauges can become stuck and/or may not be trustworthy. If the pressure is low or never changes, the system needs attention.
Many Drainback type systems need water several times a year. To check water level, look for a sight glass or other indicator. Turn the system off and wait 5 minutes or more, for the fluid to drain back to the reservoir. Add water to the full line. If there is no full line or you are in over your head…
Call Aqua Care Solar for a complete solar thermal analysis to make sure your system is working at its best.