Gasquip and Bosch review: hydropower gas hot water system tf250-8g

Friday (6 April 2018) my hot water system stopped working. It was still under warranty. It was purchased and installed 30 May 2017. I called Aztec Plumbing as they installed it and was told I would have to ring Bosch or it would cancel the warranty. I contacted Bosch and they told me I would be contacted by one of their warranty agents and they stressed that if it wasn't a warranty fault I would have to pay for a call out. GASQUIP rang me to come and have a look at it that morning. He rang me straight back to tell me that if it wasn't a warranty fault I would have to pay the call out fee of $155.00. The guy I spoke to was very rude. When he came it took him 10 minutes to fix as a spider had got into the pilot assembly. He told me that I should spray around the unit as this was a common problem. I told him that it should have been in the manual. He gave me a pensioner discount and so I paid $139.50! I contacted my gas installer and was told he would have charged me $65.00 and he also said this was a common problem. If this is such a common problem why it is not in the manual to spray for insects. I rang Bosch back to speak to someone but the girl on the phone wouldn't put me through to anyone and told me to put it here. She also told me that I shouldn't spray the unit with insect spray as it was dangerous! I think under the circumstances I am entitled to a refund of $73.50 and to rectify the issue by making it clear in the manual how to prevent this from happening.